Education for rear axles and differentials

chromebumpers

solid fixture here in the forum
Staff member
I see all these posts on picking ratios and which is the strongest but what about making old rears fit new builds? Note: These questions and answers could vary depending on application. details and questions may need to be reworded to be understood.
Where do you begin? Ads are full of rears for sale, when can they work for your application?
I have an idea that welded brackets can be cut off and new ones added but how far does that go?
We all know by now Dana 60 diffs are strong and preferred and Lots of used Dana 60 diffs with axles, usually from the front of a Ford truck are found for sale, are these modified for rear use by refitting axles and tubes? Is there such a thing as a rear too big or too heavy to use in a muscle car build? Those old GM 9.3" rears are supposed to be really strong, Ford 9" rears too, is it worth altering for a custom application or is it better just buying a new rear made to order from the factory? All these questions are assuming fair welding experience but no heavy equipment is owned or have access to, such as a mill or a lathe.
Please expect I'll be commenting after many of you replies and Re-ask questions above, I find that in the majority of multi layered questions, only the first question is either read or answered (perhaps It's better to ask one at a time).
 
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first problem, front axles from any 4x4 can,t be used as rear differentials for several reasons,
the direction of rotation the gears used,
the axles and universals all make that either difficult or physically or modifying them ,financially, or a mechanical nightmare.

http://www.4x4help.com/axle/axlevehicles2.htm00

http://chevellestuff.net/qd/rear_axle_info.htm


https://www.chevyhardcore.com/tech-stories/drivetrain/12-bolt-rearend-guide/

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Does anyone have any ideas, pictures, or links to something? [/quote]
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http://www.hotrod.com/how-to/transmission-drivetrain/ccrp-0806-chevy-chevelle-rear-axle-swap/

http://www.hotrod.com/how-to/transmission-drivetrain/dana-60-axle-review/

http://www.differentials.com/technical-help/differential-identification


keep in mind that theres semi floating and full floating rear differential housings

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MUSCLE CAR DIFFERENTIAL
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FULL FLOATING TRUCK DIFFERENTIAL

heres a darn good couple of chart's showing the effect on the cars lap time's that the selection of the correct rear gear ratio had, keep in mind this will need to be tested with every engine and drive train combo, and obviously the type of track, or speeds and tire diameter , your engines power curve, the car weight and the suspensions and tires will effect the results

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My 2500HD looks like the full floating rear pictured and I gather this is the strongest, but I never saw that huge hub on a muscle car? I don't remember seeing 8 lugs and huge hole in the center for the hub on any muscle car rim?
 
So the Dana 60 is a strong rear, does that automatically include the axle shafts? (Are the axles on par with the differential).
Are the U-joints on D60's trucks good to continue using? I read once that U-joints with lube fittings are weaker or have a higher rate of failure compared to Solid joints, true or false? At what point in Hp output must an up-grade with the drive shaft be aAż
 
I've boiled down the GTO motor dilemma to just a couple of ideas to get the job done.
One Idea:
Locate a good machine shop that favors Pontiac motors. Looking at a 1968 to 1970, high hp 455 block, purchase and assemble a package consisting of a good pair of high flow heads, crank and intake from the machine shop and have them do all the machining possible. Bring home everything and assemble everything myself. This would allow me to take pictures during assembly. Not my first choice but it gets it done.
Anyway I go I still need a capable drive-train from the flywheel back to hold up now and in the future when mods are installed.
 
http://www.chevydiy.com/history-and-identification-of-chevy-10-and-12-bolt-chevy-differentials/
btw buy new differential gears, not used ones, those are a Risky buy,
if these gears were run with poorly set up tooth contact pattern,
you will inherit noisy gears, no matter what you do.
have an experienced shop or mechanic set up the rear gears,
if they are not correctly installed they will be ruined or at least noisy
in fact your differential can differ just enough, dimensionally,
to cause new issues to come up with previously run gears from a similar differential,
that worked ok in that differential

History and Identification of Chevy 10 and 12 Bolt Chevy Differentials

http://www.mirrockcorvette.com/corvette-parts-guide-wheels.html

http://garage.grumpysperformance.co...nk-to-some-c4-corvette-wheel-tech-info.12099/
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Chevy 10- and 12-bolt axle assemblies have been standard equipment on GM passenger cars, muscle cars, and trucks for decades. The rugged, reliable, and efficient Chevy 12-bolt has established itself as the preeminent rear differential for GM muscle cars since its debut in 1965. However, the smaller 10-bolt unfairly gained the reputation as a weak and inadequate rear end for high-performance applications. But there are several models in the 10-bolt line-up. The smaller 7.5- and 8.2-inch 10-bolt rear axles can’t transmit horsepower loads in excess of 400 hp. However, the 8.5- and 8.6-inch 10-bolts are extremely stout and effective rear differentials that can transmit up to 1,000 hp to the rear wheels.
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This Tech Tip is From the Full Book, CHEVY DIFFERENTIALS: HOW TO REBUILD THE 10- AND 12-BOLT. For a comprehensive guide on this entire subject you can visit this link:
LEARN MORE ABOUT THIS BOOK HERE



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The GM 10-bolt rear end is quite possibly the most misunderstood and undervalued rear differential ever created. Even though it has been used in every major GM rear-wheel-drive platform, the 10-bolt has a bad reputation for being a low-performance unit. Nothing could be further from the truth. The 10-bolt can handle just about anything you throw at it, as long as you use the right axle, either the 8.5- or 8.6-inch. That is the great caveat; there are four sizes of 10-bolt GM rear ends: 7.5/7.625-, 8.2-, 8.5-, and 8.6-inch. These sizes refer to the diameter of the ring gear, and the one you use makes a big difference in the performance potential. The 8.5- and 8.6-inch provide superior performance and have a larger ring and pinion gear surface to handle high horsepower. Also, these surfaces run cooler because of their sheer size.



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This is the Moser Engineering 12-bolt axle assembly. As you can see, the Chevy 12-bolt differential is one stout axle, and it was the rear axle of choice for GM muscle cars and many GM competition cars. Big-block Chevelles, Camaros, and other GM high-performance vehicles were fitted with the 12-bolt limited-slip axle to maximize torque transfer and traction. (Photo Courtesy Moser Engineering)



10-Bolt Identification
You need to be able to accurately identify the GM 10-bolt. Therefore, you need be able to choose the more desirable 8.5- or 8.6-inch and avoid the smaller 7.5/7.625- and 8.2-inch units. Identifying the 10-bolt axle is easy. The nomenclature actually refers to the number of ring gear bolts. The outer cover matches; 10 bolts hold the cover onto the housing.



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This ring-and-pinion gear has suffered catastrophic failure. Be sure the mesh is correct and that the installed parts are correct so you don’t destroy components. If you take off the center section cover and discover this kind of damage, you need to identify the cause so you don’t repeat this type of failure.



8.2-Inch Units

The key to identifying the 8.2 is the shape of the housing and the spacing between the lower bolts on the cover. The 8.2 has a smooth, round lower case area, with an 11-inch cover that has a diagonal indentation at the top or a 105/8-inch irregular-shaped cover. The pinion nut should measure 11/8 inches, as long as it is the OEM pinion nut.



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Inside the 8.2, the ring gear bolts have 9/16-inch socket heads with 3/8-24 threads. The pinion diameter is 1.438 inches with 25 splines. The axles are retained by a set of C-clips on the inner end of the axle shaft inside the carrier.

8.5-Inch Units

Most 8.5-inch 10-bolts have two lugs on the bottom of the housing at the 5 and 7 o’clock positions. These should be square blocks, each with the outer side 90 degrees (vertical) to the road and the bottom-side surface horizontal to the road. The covers are often 11 inches round with a bulge on the driver’s side for the ring gear or a 105/8-inch irregular shape with the same bulge. The distance between the lower cover bolt and either adjacent bolt is 33/4 inches. The pinion nut is 11/4 inches.

The 8.5-inch differentials have 103/4-inch hex head bolts with 7/16-20-inch left-hand thread or reverse-thread bolts that hold the ring gear to the carrier. The pinion shaft diameter is 1.625 inches with 28 or 30 splines, which is the same as the GM 12-bolt design. Most 8.5 10-bolts are C-clip axles, so a set of C-clips retains the inner end of the axle shaft inside the carrier.



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Buick and Oldsmobile bolt-in axles mount at the bearing flanges on the housing ends. They retain the axle shafts in the event of a failure. The four bolts that hold the drum back plate on also retain the flange. Note that this axle has been converted to disc brakes.



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Bolt-in axles include (right to left) the axle, retainer plate, split washer shim, press-on bearing, and housing end. To remove the axle shafts, you need to remove the four bolts.



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The rear cover’s shape and the number of bolts are identifying features for GM rear differentials. The round 10-bolt cover with a bulge for the ring gear identifies this axle assembly as an 8.5-inch 10-bolt. The two lugs on the lower case at the 5 and 7 o’clock positions are also identifying features. The 8.2-inch differential does not have these lugs.



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A pair of long flat areas on the front side of each axle tube is a clear indicator of an 8.5-inch Chevy 10-bolt.



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To help you identify the 8.2-inch housing, remember that it may have an irregular-shaped cover or a round cover, but it does not have lugs as on the 8.5-inch.



A variant of this axle assembly was used in 1971–1972 Buick GSs and Skylarks, Oldsmobile Cutlasses, and some 1969–1972 Pontiac Grand Prixs, as well as the 1970–1972 Monte Carlos. These axle assemblies had bolt-in axles and were used sporadically in A-Body wagons as well. These are highly sought after, and as such, are hard to find. In this version, the axles bolt to the housing ends just as on a Ford 8- or 9-inch. This means that in the event of an axle break, the wheel stays on the car.

7.5/7.625-Inch Units

To positively identify the Chevy 10-bolt in the 7.5/7.625-inch size, you need to measure it because it is very similar to the 8.5-inch housing. The case has a similar pair of lugs at the base of the center of the housing, which are located at 5 and 7 o’clock. However, the 7.5-inch lugs are smaller, with the outer side running at an angle and the inner side cut with a radius. The oval-shaped cover measures 85/16 inches by 109/16 inches. The distance between the lower center cover bolt and its adjacent bolts is 31/4 inches. Inside, the ring gear bolts are the same as the 8.5 corporate unit. However, the pinion shaft measures 1.438 inches. The axles are retained by a set of C-clips on the inner end of the axle shaft inside the carrier.



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Chevy 10-Bolt Models

Although the 8.5- and 8.6-inch rear axles are more than capable of handling 400 hp (and with some setups a bit more), the 10-bolt name has a bad reputation due to the inherently weaker 7.5 and 8.2 designs. Because these two sizes are so common in pre-1971 (8.2) and 1975– 2002 (7.5) vehicles, the 8.5 is lumped into the same group. This design was used in all GM rear-drive cars from 1964 through 1972. The 8.2 was phased out starting in 1971; it was replaced by the 8.5-inch “corporate” 10-bolt, and was installed in everything from Camaros and Chevelles until the mid-1980s. It remained in the 1/2-ton trucks until 1999, when the 8.6 replaced it, using the same basic design.

By far, the most common 10-bolt is the 7.5/7.6, and it has been around since 1975. It was installed on small trucks and vans up to the 2005 model year. There is very little aftermarket support for this axle assembly because it couldn’t handle high-horsepower loads and therefore its performance potential was marginal. In street applications, the 7.5 is good for 350 to 400 hp with street tires and lots of wheel spin. When sticky traction bars and/or sticky tires were installed, owners found that 400 hp can quickly turn the 7.5 into shrapnel.









In the final analysis, this axle is simply too small for high-horsepower cars, and so these axles should be avoided for most muscle cars and certainly any racing applications. Although gear sets and a locking differential are available, these are only suitable for a mild street engine or possibly a dirt track car. In the world of dirt track racing, some classes require a GM 7.5-inch 10-bolt and because there is no traction on dirt, this rear works very well.

Millions of 8.2-inch axle assemblies were built and many can be found in salvage yards. And like the 7.5 axle, it has a fair amount of aftermarket support but the ring gear is too small and therefore it cannot handle much torque. If installed on a 400-hp or stronger engine, it often fails. And unfortunately, there simply isn’t enough room to install bigger axles, so it isn’t a viable option for a high-performance car. To support high torque and horsepower loads, the axle shafts need a larger diameter and spline count. Combined with the small outer bearing races, the 8.2 is limited to 28-spline axles.

For performance vehicles, the 8.2 can typically handle up to 400 hp with street tires, but that’s the limit for this axle. If you bolt on even a set of drag radials, the axles bend or break, along with having the potential for breaking the gears and carrier themselves. You can build these for performance, but if you use sticky tires, the superior traction and consequent strain from the grip will kill it quickly on the drag strip.

There are temporary fixes for the 8.2, such as a carrier girdle, but they don’t provide a reliable and suitably strong solution. When too much torque or traction is fed through the axle, it will eventually break the axle.

The 8.5- and 8.6-inch 10-bolts have larger ring-and-pinion gears, which makes an important difference. These rear axle assemblies can handle up to 400 hp. Among the Chevy 10-bolt family of axles, these provide the best performance and durability. The car versions were in production from 1971 to 1987. General Motors has been using this axle assembly in cars for 16 years and in 1/2-ton trucks for 30 years. The 2010-up Camaro uses a similar design (8.6 10-bolt) in the center section of its independent rear suspension.

The 8.5 is limited to 30-spline axles, but can withstand 1,000 hp with slicks when properly built. The factory installed the 8.5-inch 10-bolt in the Buick Grand National, and that’s the biggest claim to fame for this OEM axle. In stock form, the 8.5 can support wheel-standing launches from the turbocharged 6-cylinder. At just 3/8-inch smaller than the 8.875-inch 12-bolt differential, the 8.5-inch ring gear is strong enough for high-performance applications.

The aftermarket fully supports the 8.5. Gears of all sizes, limited-slip or Posi-Traction, lockers, and spools are offered. Affordable performance is what the 8.5 is all about. Considering the challenges of the typical 12-bolt swap for most muscle cars, when the 10-bolt units are often a bolt-in swap, the 8.5 10-bolt starts to look really good.

10-Bolt Carriers

Several differential carriers are offered for the 10-bolt axle assemblies. However, only certain gear sets are offered for the carriers, especially if you change gear ratios. Typically, 10-bolt carriers are specific to a series of gears. A 2-Series carrier holds 2.56:1 and higher gears (numerically lower) such as 2.41. These are very high gears, good for top speed, not for off-the-line performance. The 3-Series carriers are good for 2.73 and lower gears, so 3.08 and 3.73 gears work well.



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To help you identify the 8.2-inch housing, remember that it may have an irregular-shaped cover or a round cover, but it does not have lugs as on the 8.5-inch.



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In this photo, you clearly see the clutch packs with springs, so indeed these are limited-slip differentials. A Yukon aftermarket clutch-type limited-slip differential is on the left; the GM Posi-Traction differential from a 1971 Buick Gran Sport 8.5 10-bolt is on the right. As you can see, the Yukon casting is much thicker and so are the springs.



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The stock axles for both Chevy 10- and 12-bolt differentials use C-clips unless you have one of the rare bolt-in axle units. A small bolt in the center of the carrier retains the crossbar.



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The C-clips are not the strongest method for retaining the axle shafts; many owners convert the Chevy 10- and 12-bolt axles to a flange type, which retains the axle if it fails. To remove the C-clip, you push the axle in to allow room to snag the C-clip with a pick. Once the C-clip has been removed, the axle slides out of the housing.



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The placement of the casting numbers on an 8.2-inch 10-bolt varies by year and model. When you decode these numbers you can conclusively identify your axle.



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Engine torque and suspension loads are placed on the rear axle assemblies, which are also subjected to moisture, dirt, and anything the road can throw at it. You may need to clean the rear housing before you can decode the casting numbers. You can simply clean the area around the casting pad, but a power washer and some hot soapy water can work wonders for 40 years of grime.



10-Bolt Housings by the Numbers

Before you rebuild any axle, you should identify which axle you have. Once you have identified the housing, you must order the correct parts for the particular axle. The casting numbers for 10-bolt rear differentials are typically located either on the forward side of the passenger-side axle tube or on the driver’s side. These numbers are approximately 3 inches from the center section.

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The two examples at right show you how to decode 10-bolt housings.

1970 axle code: COZ 01 01 G E

COZ Ratio

01 Month

01 Day of month

G Plant

E Posi-Traction source

1971+ rear axle code: CB G 112 1 E

CB Ratio

G Plant

112 Day of year

1 Shift

E Posi-Traction source

10-Bolt Gears by the Numbers

Gears are also “coded” with their teeth count; dividing the number of ring gear teeth by the number of the pinion gear teeth yields the ratio.

A full range of pinion gears is offered for the Chevy 10- and 12-bolt axle assemblies so you are able to select the correct gear set for your vehicle, application, and setup. These are two pinion gears for the 8.5-inch 10-bolt. The pinion on the left is part of a 4.11:1 gear set; the one on the right is a 3.08:1 pinion. You can see the dramatic difference in not only teeth but in overall diameter.



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A full range of pinion gears is offered for the Chevy 10- and 12-bolt axle assemblies so you are able to select the correct gear set for your vehicle, application, and setup. These are two pinion gears for the 8.5-inch 10-bolt. The pinion on the left is part of a 4.11:1 gear set; the one on the right is a 3.08:1 pinion. You can see the dramatic difference in not only teeth but in overall diameter.



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The tooth count is stamped on the head of each pinion for both the pinion and the ring gear. As you can see, 13 is the hypoid gear countfor the pinion and 40 is the ring gear count. Pinion gears and ring gears are not interchangeable because they are designed for the specific (correct) mesh. Therefore, the specified pinion and ring gears must be used together.



The tooth count is stamped on the head of each pinion for both the pinion and the ring gear. As you can see, 13 is the hypoid gear count for the pinion and 40 is the ring gear count. Pinion gears and ring gears are not interchangeable because they are designed for the specific (correct) mesh. Therefore, the specified pinion and ring gears must be used together.









12-Bolt Identification

When it comes to GM muscle cars and sports cars, the 12-bolt axle has been the top high-performance axle assembly for decades. Compared to the Ford 9-inch, the 12-bolt positions the pinion gear higher on the ring gear. This reduces the load on the pinion, resulting in less parasitic loss from the friction and load.

The 12-bolt was introduced in 1964 and installed in cars and trucks until 1972. From 1972-on, General Motors installed its 10-bolt in cars and it remained an option for trucks until 1987.

Unlike the various 10-bolts, the 12-bolt axle assembly has different components for cars and trucks. The passenger car 12-bolt has an oval-shaped differential cover, and it measures 1015/16x 105/8 inches.



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This 1967 Chevy truck used a trailing-arm design with coil and leaf springs. The half-leaf spring (left) serves as an overload spring for heavy loads or trailering.



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General Motors installed different axles for different applications. Axles for high-performance or heavy-duty applications commonly used higher spline-count axles while common passenger car axles use lower spline counts. The top axle is an 8.5-inch 10-bolt with 30 splines; the bottom axle is an 8.5-inch with 28 splines. Note the thicker head on the bottom axle where the C-clip rides. This is specific to the carrier. The carrier and axles must match.



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General Motors used several different suspension designs in their passenger cars throughout the 1960s and 1970s. This 8.5-inch 10-bolt came from a 1971 Buick GS. The large bushings at the top of the differential housing connect to the triangulated four-bar trailing arm system that the Buick used. It is more difficult to swap these housings from car to car if they do not share the same suspension design.



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Camaros, Novas, and 1968 and later trucks used leaf springs like these. The axle may be over or under the leaf, depending on the application.



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C2 and C3 Corvettes (built from 1963 to 1981) used a non-standard 10-bolt design. They used an independent rear suspension with transverse leaf springs. As a result, these cars use a specialized axle housing for this suspension, and it’s not easily upgraded. You need to machine the housing to accept a 12-bolt carrier, which also requires custom axles. Essentially, the housing is machined to clear the larger gears and carrier, and it’s not a job for the novice.

Trucks have a smaller inner pinion shaft (1.438 inches versus 1.675 inches) and bearing, and the pinion rides lower on the ring gear. In addition, the truck 12-bolt has an irregular shape. The early truck 12-bolts had large axle splines with only 12 splines. The differential carriers are also narrower than on the passenger car units, and they do not interchange. That does not mean that the truck units are not capable of performance builds because aftermarket 30-spline carriers and axles are available.

The truck 12-bolt axles are much more affordable than the car units because they are more plentiful but these units have fewer splines so they are not as strong as the axle in the car assemblies. In addition, the trucks typically have larger axles and brakes.

Most passenger car 12-bolts used a four-bar trailing arm mounting system, with the exception of the Camaro and Nova, which used leaf springs. GM trucks from 1961 through 1967 used a two-bar trailing arm mount, while the 1968-up trucks used leaf springs. There is some crossover on the trucks, as some earlier trucks had leaves and some later trucks had the trailing arms.

All GM 12-bolts use C-clip–style axles. Aftermarket 12-bolt housings are based on the passenger car design.



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12-Bolt Carriers

The 12-bolt carriers also use the same series-specific system as do the 10-bolts; each carrier only works with certain gear sizes. The types are 2-, 3-, and 4-Series. The 2-Series is by far the most common.

12-Bolt Housings by the Numbers

The casting numbers for the 12-bolt housings are typically found on the upper rear of the driver’s side of the center section. The casting numbers are simple to decode.

The first letter is the month of the year; A is January, B is February, and so on. The next digit is the day it was built, and the last digit is the year it was built. For example, a 12-bolt axle that was built on March 28, 1967, is C287.



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The Chevy 12-bolt axle assemblies for passenger cars feature an oval cover with a diagonal indentation. This is a 1969 Chevelle 12-bolt housing.



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Truck 12-bolts have an irregular cover with a ring gear pocket. This example is a 1967 Chevy C10. The truck housings are not as durable as the passenger car housings due to a narrower carrier and a smaller inner pinion bearing.



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On the passenger-side front tube, the stamped axle code designates either 1969-and-earlier units or 1969-and-later builds. The 1969- and-earlier codes have two letters, then a four-digit number, followed by a letter, and possibly a shift number, for which 1 is the day shift and 2 is the night shift.

And finally, a Posi-Traction number was used.

For 1969 and later, the code typically features six to eight digits, including three letters, three numbers, and sometimes an additional number and letter. The first two letters indicate the gear-ratio code, the third letter notes the build plant, and three numbers designate the build day from 001 to 365. Sometimes the shift code is stamped, and if the unit has a Posi-Traction, you see a P stamp.
 
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MICK53 said:
I bought a used Frankland rear end for my 53 1/2 ton pickup. I took it to the Frankland factory in PA to have it rebuilt with Gleason locker and retubed with 12 bolt flanges to fit under my truck. They would not get axles for me. They told me to call Strange Engineering. I called Strange and explained to them that I needed axles to accept 12.88 Wilwood disk brakes. They told me that they could not help me until I filled out an online form. It wanted information I had no idea about such as axle diameter and bearing size. When I explained to them I had no axles to start with they were kinda rude to me. So I called the engineer at Wilwood (Erik) that I have been working with and he suggested I call Moser. It turns out that they are only 2 hours from my house. When I called Moser they said no problem and If I could get it there by 8am any day that they should be able to get it done by that afternoon. I loaded up the rear end and the brake kit so everything would be right and planed to leave the next morning at 6am. That night we had 4" of snow and freezing rain. It was almost 10am by the time I got there. When I backed the truck in to drop it off they discovered that Frankland had put the wrong flanges on and welded them on backwards, inside out. I asked them if they could fix it or send it somewhere to get it right. They asked me to wait a little while and they would check it out. At about 11am they told me they could replace the flanges and have me done around 3pm if I wanted to wait. So I went in town and killed some time. By 2pm they had removed the old flanges and welded on new ones. They had the axles done also. Then they took me out to the shop and installed one of the brakes to show me how they went. There were some bolts that the kit called for using existing bolts that I didn't have. They had the special flange bolts. Also the roter holes had to be enlarged for the studs. By 3pm I was on the road. They charged me an extra $100 for the flanges, bolts and extra labor. More than fair in my mind. In this day and age it is very seldom that I get this kind of service. I would highly recommend Moser for anything they do.

grumpyvetteAdministratorStaff Member
there have been guys that have the financial resources or connections and or skills to have built an independent rear differential , based on the far stronger DANA 60 vs the factory supplied dana 36 or dana 44 , which are comparable to the G.M. 10 bolt rears, hardly impressive or known for strength or durability, to fit the corvette frame, obviously this takes a good deal of time,effort and money but it also can result in an exceptionally strong rear differential
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yes its very unfortunate that there's no commonly, available, and reasonably priced, independent rear differential,available to the performance car enthusiasts,with large disc brakes in the compatible width, and easily retro fitted suspension mounts that I'm aware of, in most local salvage yards , similar to the corvette rear suspension, that has the strength of the dana 60 rear differential.
yes there are custom fabricated solutions, if you have a very healthy bank balance , but nothing based on a dana 60-70- or ford 9" or heavier duty independent G.M. differential

http://www.wallaceracing.com/driveshaftspeed.php
http://www.dennysdriveshaft.com/c976_combination_universal_joints.html
http://pstds.com/critical-speed-chart/

http://www.wolferacecraft.com/pinionangle.aspx

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http://azdriveshaft.com/
You'll need to consider the materials its made from,
the diameter of the drive shaft tube,
and the torque loads its expected to handle, and rpms it will need too transmit as it turns
, naturally as both torque, loads, and rpms increase the strength,
of the materials and yoke and bearing size and resulting cost to build it from quality materials,increases.
As you will see looking over the chart below,a 44"-60" increase in length , results in a very large reduction in the recommended rpm range, as the length increased,and its a big mistake to assume youll get by with inferior materials or workmanship or without having the drive shaft properly balanced.
youll see few performance cars with two piece drice shafts but at times its required.
heres a bit of related info below


Driveshaft Tech and FAQ

Operating Angle
Operating angles in a driveshaft are the angles between the pinion, driveshaft and transmission centerlines. The optimal angle for any driveshaft to run at is 1/2 degree, where many vibrational and frictional problems are non-existent. In order to minimize power loss and vibration in an offset configuration, the pinion centerline and the transmission centerline need to be parallel. In general, the largest angle for racing applications should 2 degrees and the centerlines should be parallel within 1/2 degree. With suspension movement the operating angle will increase, but should not exceed 15 degrees. If the centerlines are off too far, the u-joints travel at uneven operating velocities, causing vibration (this is the same problem induced by poorly phased end yokes). This vibration is hard to distinguish from an unbalanced driveshaft.

shaftangle.jpg


Critical Speed
Critical speed is the speed at which a spinning shaft will become unstable. This is one of the single largest factors in driveshaft selection. When the whirling frequency and the natural frequency coincide, any vibrations will be multiplied. So much that the shaft may self destruct. Another way to think of this is that if a shaft naturally vibrates at 130 times a second, and one point on the shaft passes through 0 degrees 130 times a second (7800 RPM) then the shaft has hit a critical speed. There are several ways to raise the critical speed of a driveshaft. You can make it lighter, stiffer, or increase diameter without increasing weight. This is the reason carbon fiber makes a good driveshaft, it is stiff and light and can be made to any diameter or wall thickness. Aluminum, while it has a very good critical speed is not quite as strong as steel. Steel, with good strength characteristics will have a lower critical speed.

critspeed.jpg

THANKS FOR POSTING THE INFO
it sounds like the guys at moser will be getting my future business

I've dealt with far to many people that cop a
"I JUST DON,T GIVE A S^&^&& attitude if they can,t simply grab something off a shelf"

http://www.moserengineering.com/faqs/

http://garage.grumpysperformance.co...ear-axles-and-differentials.11848/#post-73266

http://www.moserengineering.com/contact/

http://www.moserengineering.com/rear-ends-housing-and-axles.dept?page=all

http://www.moserengineering.com/
 
Last edited:
I put Moser axles in the TBucket after my right axle decided to exit the housing a couple of
years ago. I didn't have near the complications as Mick53 above to text them with, but I would
buy from them again. I did have a conversation with them and he steered me away from an
option I didn't need.
 
Suspension Measurements


The following list of extensive information was contributed by R. Welch:

Original Vehicles
Rear Suspension Width (Flange to Flange)


Year

Classic Vehicles

Width

26-39

Plymouth-Dodge car/pick up

56-58"

40-52

Plymouth-Dodge car

60-62"

26-39

Chrysler/DeSoto Car

60"

Most Early

Mopar's

56-62"

25-39

Chevy Car

56-58"

26-46

Chevy Truck

56-58"

40-48

Chevy Car

58-60"

49-54

Chevy Car

58-60"

47-54 & 55 1st Series

Chevy Truck

60-62"

Most Early

Buick,Olds, Pontiac

58-61"

28-31

Ford Car/Pickup

57 1/2"

32 & 33-34

Ford Car/Pickup

56 1/2"

35-48

Ford Car

57-60"

35-41

Ford Pickup

56-60"

49-58

Ford Car

57-58"

49-56

Mercury

57-58"

49-51

Mercury

61"

64

Falcon

58"

67

Cougar

60"

55-59

Chevy Pickup

62"



Donor Vehicles Front and Rear
Suspension Width (Flange to Flange)


Year

Classic Vehicles

Width Front

Width Rear

74-79

Ford Mustang II/Pinto & Mercury Capri/Bobcat

55 ½"

55 ½"

71-77

Ford Maverick with 8" axle

56 ½"


75-80

Ford Granada with 8" axle

57 ½"


64-66

Mustang

57"


67-71

Mustang

59"


72-73

Mustang

60"


67-69 , & 60"

Camaro

60"


64-67

Chevelle

60"


55-64

Chevy car

60"


65-67

Nova

58"


68-72

Nova

60"

60"

78 & up

Monte Carlo, Regal, etc. with 10 bolt axle

58"

58"

68-72

Chevelle with 10 bolt axle

61 ½"


89

Trans AM (Disc brake)

62"


76-80

Camaro/Firebird

61 ½"

60 ½"

68-83

Corvette

58 ½"

59 ½"

84-95

Corvette

59 ½"

60 ½"

Early 70's

"A" body (Dart/Duster) with V8&3/4 axle

58"



"E" Body (Cuda) with V8&3/4 axle

58"



Dodge Dart

59"

55 ½"


Plymouth Volare & Dodge Aspen

61"

60 ½"

71

Blazer (6 lug)

63 ¾"


75-78

Granada 9"

(43" perch to perch)

52 ¼"

75-78

Maverick 9"

(43" perch to perch)

56 ¼"

81-87

Olds Cutlass

58 ½"
 
GTO Axle Identification
https://fuelandfriction.com/weekend-warrior/understanding-rear-differential-noise/
Overall Housing Dimensions

Size for the standard mid-year 1966 and later GTO differential is as follows:

Axle flange to axle flange is 60 15/16 inches
Backing plate to backing plate is 55 1/2 inches
Spring perch centerline to centerline is 35 inches
Shock mount centerline to centerline is 49 1/4 inches.

Subtract 1" from above measurements for production mid-year 1966 and earlier

No wider unit should be used, but a narrower unit can easily be used with the bonus of using a standard wheel offset. (A suggested GTO maximum wheel width with standard axle is approximately 8". This means the rim is 9" wide from outside rim to outside rim. In order to fit properly with the stock axle, a wheel with 5" backspacing will give 4" to the outside of the rim from the mounting surface. A 2 inch narrower axle would allow a normal rim to be used with no offset.)

GETTING WIDE TIRES TO FIT:

Bolt pattern is 5 on 4.75" same as Chevy Malibu - so very common wheel. What's not so common is the required back spacing to get the wheel centered in our wheel wells if you plan on running fatter tires in the rear. Mid 1966 to 1972 Rear axle is about 61" axle flange to axle flange (where brake drums butt up against), but early 66's before about January production were only 60". The current axle needs to be measured to verify width, because it plays an important part in determining what rim backspacing is necessary. The later rear axle requires a wheel with between 5" and 5-1/4" of backspacing, while the earlier axles will only need a wheel with 4-1/2" to 4-3/4" backspacing.


Next thing is to get the maximum width out of the back wheel tubs. The inside is easy since a mallet will smash in the inner fender sheet metal above the frame rail until it is slightly further away from the wheel than the frame rail. Even if there is rubbing, it will be on a totally smooth surface. Only the very bottom metal needs to be moved over, and nothing needs to be done up higher. Outside edge is much more work. For some reason Pontiac decided to use a 2" wide lip on the wheel well, and about half this lip has to be removed. After the lip is trimmed back, the only thing the tire can touch is the smooth rolled edge of the inner wheel well about 2" above the lip. Easiest way to properly trim things back is to start by drilling new screw holes through the stainless molding a half inch more to the outside of the current screw holes. Drilling one hole at a time and moving each screw will keep things in line. After all holes have been made and the screws all fit, take off the molding and draw a line from each of the old screw holes to the next - this will be the cutting line for removing about 3/4" of lip. If you cut past the screw holes, there is a very good chance that you will remove the spot welds keeping the inner fender attached to the quarter panel. We have done about a dozen cars cutting up to the old screw holes and never had a problem. This process usually goes pretty fast using a cut-off wheel, but it is terribly messy and really good eye protection is necessary. If you have any doubts, a body shop could handle the cutting and it should only take an hour of shop time. The stainless molding can then be cut between the screw holes to match the fender lip. A good pair of tin snips can be used for this trimming. A little sanding of the edges will prevent future cuts and snags.


When the above is completed, the width of the wheel well will go from about 10-1/2” to exactly 12” on the early GTO's, and even wider on the 1968 to 1972 models. At this point a 275/60R15 tire can be installed using rims with the proper backspacing. This tire mounted on an 8” rim will be approximately 11” wide, leaving about a half inch on each side of the tire on an 8” rim. A wider rim will also make the tire wider. Figure something like .6” increase in width for each inch of rim width increase.


Our GTO’s came new from the factory with a droopy rear end, and things haven’t improved over the years. A one inch spacer installed under the rear springs will bring the car up to level ride height. A 1-1/2” spacer will provide a very mild “California Rake” to the front. Neither spacer will affect ride quality since it is under the spring and won’t change the spring rate. Anything over a 2" lift at the rear springs might result in wheel hop, and anything over 2-1/2" you're pretty much going to get hop for sure.


10 Bolt Axle Ratio Identification:

Three different differential carriers are used.

1) 2.56 and 2.78 ratios
2) 2.93, 3.08, and 3.23 rations
3) 3.36, 3.55, 3.90 and 4.33 ratios.

There was also a stronger 4 pinion spider gear carrier installed on 4-speed cars.

Codes are as follows:

Note "W" on the code is for standard differential, while "Y" on the code is for locking differential or "Posi" rear ends. The following codes appear on the left hand axle tube approximately 2” to the left of the brake tube holder, or about 6” to the left of the differential case. They are about mid height.

GTO: WB or YB 2.56 (41:16)
WC or YC 2.78 (39:14)
WD or YD 2.93 (41:14)
WE or YE 3.08 (40:13)
WF or YF 3.23 (42:13
WG or YG 3.36 (37:11)
WH or YH 3.55 (39:11)
WK or YK 3.90 (39:10)
YL 4.33 (39:9)



Some 12 Bolt Carrier Identification data:

12 bolt ED32088 ..............2 series......... 2.73:1 & down
12 bolt 30140PM1.............3 series........3.08:1 to 3.73:1
12 bolt EDB30174............. 4 series....... 3.90:1 & up

12-bolt%20carrier.jpg




Manual Transmission Gears

Muncie transmissions:

FM on Pontiac or FO on Tempest identifies the wide ratio transmission. There are two bands on the input shaft of a wide ratio trans.

2.52 Low
1.88 Second
1.46 Third
1.00 Fourth
2.59 Reverse

FN on Pontiac or FT on Tempest identifies a close ratio transmission. There is only one milled band on the input shaft of a standard close ratio trans, and no bands on a Rock Crusher.

2.20 low
1.64 Second
1.46 Third
1.00 Fourth
2.27 Reverse
 
Last edited:
Rear axle widths
These dimensions do not include brake drums and are measured from backing plate to backing plate. Actual wheel track could be as much as 6" to 8"depending on drum size:
46" to 47"
'66 to '77 Bronco

48" to 49"
'72 to '75 Datsun pickup
'71 Dodge Colt
'72 to '73 Mazda

50" to 51"
'73 to '76 A-Body Mopar
'65 AMC American
'58 to '60 Thunderbird

52" to 53"
'28 to '40 Ford
'57-'59 Ford and Edsel
'63-'69 Falcon/Comet
'63 to '65 Fairlane
'65 to '66 Mustang
'62 Buick Skylark
'67 to '70 Mustang/Cougar 6 cyl.
'71 to '74 Maverick/Comet
'71 to '72 Pinto
'68 to '69 AMX and Javelin
'63-'72 A-Body Mopar except 8 ¾" axle
'75 to '79 Granada/Monarch

54" to 55"
'39 to '48 Chevrolet
'41 to '48 Ford
'55 to '57 Chevrolet
'68 to '69 Fairlane
'67 to '70 Mustang/Cougar 8 cyl.
'62 to '70 B-body Mopar w/ 8 ¾" or 9 ¾" axle
'79 to'85 Toyota pickup
'68 to '72 Chevelle
'74 to '79 Mustang II/Pinto/Capri/Bobcat

56" to 57"
'70 to '71 Torino/Cyclone
'71 to '73 Mustang/Cougar
'60 to '64 Ford full-size
'61 to '67 Thunderbird
'58 to '72 Ford F-100 pickup
'26 to '39 Plymouth/Dodge
'40 to '52 Plymouth/Dodge
'67 Lincoln
'69 Dodge Van
'54 to '56 Ford pickup
'26 to '46 Chevy truck
'25 to '39 Chevrolet cars
'28 to '34 Ford cars and pickups
'49 to '56 Ford/Mercury car
'71 to '74 B-body and E-Body Mopar
'63 to '70 Chrysler C-body cars
'75 to '78 Maverick/Comet
'75 to '76 Dart

58" to 59"
'73 to '90 Ford F-100/150 pickup
'61 Chevrolet full-size
'65 Cadillac
'66 Buick full-size
'66 to '67 Chevrolet full-size
'69 Oldsmobile full-size
'72 to '73 Torino
'40 to '54 Chevy cars
'35 to '48 Ford
'35 to '41 Ford pickup
'55 to '59 Chevy pickup
'71 to '74 B-body station wagon
'71 to '74 Chrysler C-body cars
'86 to '95 Toyota pickup
'78 to '86 Monte Carlo/Century
'68 to '83 Corvette
'68 to '74 Apollo
'78 to '86 Grand Prix
'76 to '80 Scout with 9" axle
'78 to '80 Bronco with 9" axle

60" to 61"
'26 to '39 Chrysler/Desoto
'47 to '55 Chevy pickup
'70 to '72 Lincoln Continental
'68 to '74 Nova/GTO
'76 to '80 Camaro and Firebird
'84 to '95 Corvette
'76 to '80 Aspen and Volare
'74 to '77 Jeep pickup

These measurements are from brake drum to brake drum:
56-1/2"
'74 Maverick

57"
'75 Mustang II

57-1/4"
'65 to '66 Mustang
'57-'64 Ford full-size
'57 to '59 Ranchero and station wagon

58"
'66 to '77 Bronco
'64 Falcon

58-1/2"
'77 to '81 Granada and Lincoln Versailles

59-1/4"
'67 to '70 Mustang
'67 to '71 Comet, Cougar, Fairlane

60"
'67 Cougar

61-1/4"
'71 to '73 Mustang
'67 to '73 Torino/Ranchero with 9 ¼" axle

63-1/2"
'67 Fairlane with coil springs

65-1/4"
'73 to '86 Ford ¾ ton Van

68"
'72 Ford ¾ ton Van
 
Note: All measurements are in inches unless otherwise noted.

https://www.musclecardiy.com/performance/axle-shaft-selection-for-optimal-performance/

https://www.chevydiy.com/history-and-identification-of-chevy-10-and-12-bolt-chevy-differentials/

https://www.differentials.com/technical-help-2/differential-identification/

https://www.google.com/search?q=gm+10-bolt+rear+end+casting+numbers&rlz=1C1CHZN_enUS928US928&sxsrf=AOaemvKL4D74Ej9XI6Ul3Hu4Vz6yDw8ENQ:1632880986657&tbm=isch&source=iu&ictx=1&fir=C0PPs3XYMpGCuM%2CElzukigSyIsdVM%2C_%3BGO8L_xdnJjMjRM%2CElzukigSyIsdVM%2C_%3BMD31zPJtfP5KYM%2CElzukigSyIsdVM%2C_%3BK1nqsEfwVAnTEM%2CElzukigSyIsdVM%2C_%3Bq1b3qgfK8wGpNM%2CElzukigSyIsdVM%2C_%3BFMw9_HRMa6s31M%2CElzukigSyIsdVM%2C_&vet=1&usg=AI4_-kTVnvgtYqQuy1ca8loKb9eO1YAogA&sa=X&ved=2ahUKEwiux63Zi6PzAhVtSzABHTRPDpgQ_h16BAgNEAE#imgrc=K1nqsEfwVAnTEM

GMaxles.jpg


https://www.chevyhardcore.com/tech-stories/drivetrain/10-bolt-chevy/
32.jpg


This article will be divided into at least three sections

The first section will list wheelbase, front track and rear track of vehicles in inches, so that those interested in frame swaps or clip swaps can find the correct donor vehicle. Dimensions will be listed left to right as wb/ft/rt followed by the year, make and model of the vehicle. For instance: 86.0, 50.6, 50.3 -- 1952 Morris Minor. If one or more of the dimensions are unknown, NA should be inserted in that space. For instance, if the wheelbase of the Morris were unknown, it would be listed as NA, 50.6, 50.3 -- 1952 Morris Minor. If the wheelbase were known, but the front and rear track were unknown, it would be listed as 86.0, NA, NA -- 1952 Morris Minor.

Guide for taking measurements
Most often, wheelbase is the dimension from the center point at the end of the front axle or spindle to the center point of the end of the rear axle. Note that the measurement could also be described as being between the center points of the circles described by the front and rear wheels on the same side of the vehicle.

Track is the dimension from the centerline of the tire tread on one tire to the centerline of the tire tread on the opposite tire on the same end of the vehicle. E.G.: Front track or rear track. On vehicles with dual wheels, that measurement is commonly taken from halfway between the centers of each tire on both right and left sides. There are also "Inner track" and "Outer track" dimensions, measured from the center lines of the inner tires and the outer tires of the dual wheel axle.

The second section will be listed as axle flange to axle flange where the wheel bolts on. Drum to drum would be close enough to the same if that's all the information you have to post. The only difference between the two would be the thickness of the material of the two drums or brake rotors/discs at the studs.

The third section will list backing plate to backing plate on the rear differential. This information will require knowing the width of the brake drum to determine flange to flange dimensions. Find brake drum width, multiply X two and add that figure to the plate to plate dimension to get flange to flange.

Wheelbase, front track, rear track
American Motors
  • 100.0", 61.2", 60.2" -- 1975 AMC Pacer
100.00, aprox 57, 57 58-60 American

GM car
  • 122.0", 58.31", 59.25" -- 1937 Buick Special
  • 126.0", 58.31", 59.25" -- 1937 Buick Century
  • 124.0", 58.0", 59.0" -- All 1950 to 1954 GM 4 door cars
  • 122.0", 59.0", 61.5" -- 1949-'50 Oldsmobile 98
  • N/A, 59.1", 58.8" -- 1968-'74 Buick Apollo
  • 112.0" (coupe); 116.0" (sedan,wagon); 61.5", 60.7" -- 1973-'77 Buick Regal
  • 111.0", 59.1", 59.7" -- 1975 Buick Skylark
  • N/A, 59.0", 58.8" -- 1978-'86 Buick Century
  • 115", 56.69", 58.75" -- 1949-'54 Chevy & Canadian Pontiac
  • 115.0", 58.5", 60.0" -- 1955-'57 Chevy
  • 108.1", 58.7", 60.5" -- 1967-'69 Chevy Camaro (other source shows 108.1/59.0/58.9)
  • 108.1", 60.4", 61.0" -- 1970 Chevy Camaro
  • 108.1", 58.9", 59.5" -- 1970-'73 Chevy Camaro Z-28
  • N/A, 61.3", 60.5" -- 1976-'80 Chevy Camaro Z-28, Pontiac Trans Am
  • 101.1", 60.7", N/A -- 1993-'02 Chevy Camaro
  • 101.0", 60.7", 60.6" -- 1986 Chevy Camaro IROC Z
  • 101.1", 60.7", 60.7" -- 1998 Chevy Camaro
  • 112.3", 63.7", 64.1" -- 1999 Chevy Camaro LS, LT
  • 112.3", 63.7", 63.7" -- 1999 Chevy Camaro SS
  • 119.0", 62.5", 62.4" -- 1965-'70 Chevy Caprice
  • 119.0", 62.5", 62.5" -- 1961 Pontiac Catalina, Ventura
  • 121.5", N/A, N/A -- 1971-'76 Chevy Caprice coupe/sedan
  • 123.0", 62.5", 62.5" -- 1961 Pontiac Bonneville, Star Chief
  • 125.0", N/A, 64.5" -- 1971-'76 Chevy Caprice station wagon
  • 116.0", N/A, N/A -- 1977-'90 Chevy Caprice
  • 115.9", 61.8", 60.7" -- 1991-'96 Chevy Caprice
  • 112.0" (coupe); 116.0" (sedan,wagon), 61.5", 60.7" -- 1973-'77 Chevy Malibu, Laguna
  • 102.0", 57.0", 59.0" -- 1954-'62 Chevy Corvette
  • N/A, 58.7", 59.5" -- 1968-'82 Chevy Corvette
  • N/A, 59.6", 60.4" -- 1984-'95 Chevy Corvette
  • 108.0", 58.5", 58.8" -- 1978-'88 Chevy Monte Carlo, Malibu, El Camino (117.1 wheelbase), Olds Cutlass, Pontiac Grand Prix
  • 111.0", 59.8", 59.6" -- 1968-'74 Chevy Nova
  • 97.0", 54.7", 53.6" -- 1971-'77 Chevy Vega, 1973-'77 Pontiac Astre, 1975-'80 Chevy Monza, Buick Skyhawk, Olds Starfire, 1976-'80 Pontiac Sunbird
  • 112.0" (coupe); 116.0" (sedan,wagon), 61.5", 60.7" -- 1973-'77 Oldsmobile Cutlass, 442
  • 112.0" (coupe); 116.0" (sedan,wagon), 61.5", 60.7" -- 1973-'77 Pontiac Grand Prix, LeMans
  • N/A, 58.9", 59.0" -- 1978-'86 Pontiac Grand Prix
  • 115.0", N/A, N/A -- 1966 Pontiac GTO
  • N/A, 59.9", 59.6" -- 1968-'74 Pontiac GTO
  • 112.25", 57.5", 59.0" -- 1939-'40 Chevy w/knee action shocks
  • 112.25", 56.375", 59.0" -- 1939 Chevy w/I-beam front end
  • 116.0", 57.6", 60.0" -- 1941-'48 Chevy
GM truck
Note: Measurements in inches

  • 115.0, 127.0, 133.0 -- 1960-'72 Chevy Pickups
  • 115.0 -- 1960-'66 Chevy and GMC Suburban
  • 106.5, 64.5, 63.0 -- 1973-'91 Chevy Blazer 2WD
  • 106.5, 65.75, 62.75-- 1973-'91 Chevy Blazer 4WD
  • 131.5, 65.8, 62.7 -- 1973-'87 Chevy C-10, K-10
  • 131.5, 65.8, 62.7 -- 1973-'87 Chevy C-20, K-20, C30
  • 164.5, 65.8, 62.7 -- 1973-'91 Chevy C-30, K-30 Crew Cab
  • 129.5, 65.8, 62.7 -- 1973-'91 Chevy Suburban
  • 114.5, 60.52,61.02 -- 1955 Chevy 2nd. series (1955 1st. series was same as 1954)
  • 116.0, 59.5, 60,, -- 1947-'54 Chevy AD 1/2 ton
  • 125.25, 62.6, 52.1 -- 1947-'54 Chevy AD 3/4 ton
  • 137.0, N/A,,, N/A,, -- 1947-'54 Chevy AD 1 ton
  • 144.0, N/A,,, N/A,, -- 1902 Chevy Silverado 1500 4WD
  • 102.4, N/A,,, N/A,, -- 1972-'80 Chevy LUV w/standard cab and 73.1" box (unequal length A-arms with torsion bars was standard front suspension on LUV)
  • 104.3, N/A,,, 54",, -- 1981-'82 Chevy LUV w/standard cab and 73.1" box (unequal length A-arms with torsion bars was standard front suspension on LUV)
  • 117.9, N/A,,, 54",, -- 1978-'82 Chevy LUV w/standard cab and 90.1" box (unequal length A-arms with torsion bars was standard front suspension on LUV)
  • 100.5, 54.5, 54.7 -- 1983-'01 Chevy S-10 Blazer 2-dr., 1983-'01 GMC Jimmy 2-dr. Two wheel drive.
  • 107.0, 54.5, 54.7 -- 1990-'01 Chevy S-10 Blazer 4-dr., 1990-'01 GMC Jimmy 4-dr. Two wheel drive.
  • 108.3, 54.5, 54.7 -- 1982-'93 Chevy S-10 standard cab, 73" box, 1982-'93 GMC reg cab, 73" box (stock Malibu and El Camino spindles are bolt-on) two wheel
  • 117.9, 54.5, 54.7 -- 1982-'93 Chevy S-10 standard cab, 89" box, '82-'93 GMC regular cab, 89" box two wheel
  • 122.9, 54.5, 54.7 -- 1983-? Chevy S-10 extended cab, '83-? GMC Sanoma extended cab two wheel drive.
  • 108.3, 57.22, 57.22 -- 1982-'93 Chevy S-10 standard cab, 73" box, 1982-'93 GMC reg cab, 73" box (stock Malibu and El Camino spindles are bolt-on) four wheel
  • 117.9, 57.22, 57.22 -- 1982-'93 Chevy S-10 standard cab, 89" box, '82-'93 GMC regular cab, 89" box four wheel
  • 122.9, 57.22, 57.22 -- 1983-? Chevy S-10 extended cab, '83-? GMC Sanoma extended cab four wheel drive.
  • 122.9, 61.12, 61.12 -- 1994 - 2003 chevy zr2 extended cab, four wheel drive.
  • 135.0, 67.8, 67.8 -- 2008 Chevy Express Cargo 1500 work van
  • 111.2, 57.48, 57.48, -- 2004 - '12 Chevy Colorado reg. cab two wheel drive
  • 126 , 57.48, 57.48, -- 2004 - '12 Chevy Colorado ext. cab two wheel drive
  • 111.2, 59.65, 59.65, -- 2004 - '12 Chevy Colorado reg. cab four wheel drive
  • 126 , 59.65, 59.65, -- 2004 - '12 Chevy Colorado ext. cab four wheel drive
  • 113, 63.1frt-62.1rear-- 2002-2009 Chevy Trailblazer
  • 129, 63.1frt-62.1rear-- 2002-2009 Trailblazer EXT
Ford car
  • 108", 56.0", 56.0" -- 1964-'68 Mustang
  • 96.2", 55.6", 55.8" -- 1974-'79 Ford Mustang II, Ford Pinto, Mercury Bobcat, Mercury Capri (track also listed as 55.1"/55.3")
  • 100.5", 56.6", 57.0" -- 1986 Ford Mustang GT
Ford truck (wheelbase only)
1953-'55

  • F100 1/2-ton - 110"
  • F250 3/4-ton - 118"
  • F350 3/4-ton - 130" (F350 was still classified as 3/4 ton trucks through '55)
1956-'60

  • F100 1/2-ton SWB - 110"
  • F100 1/2-ton LWB - 118"
  • F250 3/4-ton - 118"
  • F350 1-ton - 130"
1961-'63

  • F100 1/2-ton SWB - 114"
  • F100 1/2-ton LWB - 122"
  • F250 3/4-ton - 122"
  • F350 1-ton - 132"
1964

  • F100 1/2-ton SWB - 114"
  • F100 1/2-ton LWB - 128"
  • F250 3/4-ton - 128"
  • F350 1-ton - 132"
1965-'66

  • F100 1/2-ton SWB - 115"
  • F100 1/2-ton LWB - 129"
  • F250 3/4-ton - 129"
  • F250 3/4-ton Crew Cab - 147"
  • F350 1-ton - 132"
  • F350 1-ton Crew Cab - 152"
1967-'68

  • F100 1/2-ton SWB - 115"
  • F100 1/2-ton LWB - 131"
  • F250 3/4-ton - 131"
  • F250 3/4-ton Crew Cab - 147"
  • F350 1-ton - 132"
  • F350 1-ton Crew Cab - 152"
1969-'70

  • F100 1/2-ton SWB - 115"
  • F100 1/2-ton LWB - 131"
  • F250 3/4-ton - 131"
  • F250 3/4-ton Crew Cab - 147"
  • F350 1-ton - 135"
  • F350 1-ton Crew Cab - 159.5"
1971

  • F100 1/2-ton SWB - 115"
  • F100 1/2-ton LWB - 131"
  • F250 3/4-ton - 131"
  • F250 3/4-ton Crew Cab - 159"
  • F350 1-ton - 135"
  • F350 1-ton Crew Cab - 159.5"
1972

  • F100 1/2-ton SWB - 115"
  • F100 1/2-ton LWB - 131"
  • F250 3/4-ton - 131"
  • F250 3/4-ton Crew Cab - 159"
  • F350 1-ton - 135"
  • F350 1-ton Crew Cab - 159"
1973

  • F100 1/2-ton SWB - 117"
  • F100 1/2-ton LWB - 133"
  • F250 3/4-ton - 133"
  • F250 3/4-ton Crew Cab - 161"
  • F350 1-ton - 137"
  • F350 1-ton Crew Cab - 165.5"
1974

  • F100 1/2-ton SWB - 117"
  • F100 1/2-ton LWB - 133"
  • F100 1/2-ton SuperCab LWB 6-ft. bed - 140"
  • F100 1/2-ton SuperCab LWB 8-ft. bed - 155"
  • F250 3/4-ton - 133"
  • F250 3/4-ton SuperCab - 140"
  • F250 3/4-ton Crew Cab - 155"
  • F350 1-ton - 137"
  • F350 1-ton SuperCab - 140"
  • F350 1-ton Platform/Stake - 161"
  • F350 1-ton Crew Cab - 166.5"
1975

  • F100 1/2-ton SWB - 117"
  • F100 1/2-ton LWB - 133"
  • F100 1/2-ton SuperCab 6-ft. bed - 140"
  • F100 1/2-ton SuperCab 8-ft. bed - 155"
  • F150 1/2-ton - 133"
  • F250 3/4-ton - 133"
  • F250 3/4-ton Crew Cab - 155"
  • F350 1-ton - 137"
  • F350 1-ton Platform/Stake - 161"
  • F350 1-ton SuperCab - 155"
  • F350 1-ton Crew Cab - 166.5"
1976

  • F100 1/2-ton SWB - 117"
  • F100 1/2-ton LWB - 133"
  • F100 1/2-ton SuperCab - 155"
  • F150 1/2-ton - 133"
  • F250 3/4-ton - 133"
  • F250 3/4-ton Crew Cab - 155"
  • F350 1-ton - 137"
  • F350 1-ton SuperCab - 155"
  • F350 1-ton Crew Cab - 166.5"
1977

  • F100 1/2-ton SWB - 117"
  • F100 1/2-ton LWB - 133"
  • F100 1/2-ton SuperCab - 155"
  • F150 1/2-ton - 133"
  • F150 SuperCab - 155"
  • F250 3/4-ton - 133"
  • F250 3/4-ton Crew Cab - 155"
  • F350 1-ton - 137"
  • F350 1-ton SuperCab - 155"
  • F350 1-ton Crew Cab - 166.5"
1978-'79

  • F100 1/2-ton SWB - 117"
  • F100 1/2-ton LWB - 133"
  • F100 1/2-ton SuperCab - 155"
  • F150 1/2-ton - 133"
  • F150 SuperCab - 155"
  • F250 3/4-ton - 133"
  • F250 3/4-ton SuperCab - 155"
  • F250 3/4-ton Crew Cab - 155"
  • F350 1-ton Camper Special- 140"
  • F350 1-ton SuperCab - 155"
  • F350 1-ton Crew Cab - 166.5"
Mopar car
  • 126.0", 60.4", 59.6" -- 1956 Chrysler Windsor & New Yorker Sedans & Hardtops
  • 115.0", 61.9", 62.0" -- 1975 Chrysler Cordoba
  • 109, 58.9", 59.0" -- 1975-'79 Dodge Aspen, Plymouth Volare
  • 111.0", 59.2", 55.6" -- 1967-'76 Dodge Dart, Plymouth Scamp
  • 108.0", 59.2", 55.6" -- 1970-'76 Dodge Demon/Dart Sport, Plymouth Duster
Miscellaneous
  • 105.0", 58.0", 58.0" -- 1951 Cunningham C-1, C-2R
  • 107.0", 58.0", 58.0" -- 1953 Cunningham C-3
  • 100.0", 54.0", 54.0" -- 1952 Cunningham C-4R, C-4RK
  • 100.0", 55.0", 55.0" -- 1953 Cunningham C-5R
  • 100.0", 52.0", 52.0" -- 1955 Cunningham C-6R
  • 086.0", 50.5", 50.3" -- 1948-'74 Morris Minor
Rearend widths
Chevrolet
Outside Width (in.) Year Model
57.75 1962-1964 Chevy II/Nova
57.75 1965-1967 Chevy II/Nova
58.00 1978-1988 Chevy Malibu, Monte Carlo
59.00 1937-1939 Chevy car
59.50 1968-1982 Corvette
60.00 1955-1964 Chevy car
60.00 1967-1969 Camaro
60.25 1968-1979 Chevy II/Nova
60.50 1984-1995 Corvette
60.50 1964-1967 Chevelle
62.00 1955-1959 Chevy pickup
62.50 1968-1972 Chevelle
61.00 1970-1981 Camaro/Firebird

Ford
Outside Width (in.) Year Model
56.50 1969-1977 Maverick 8"
57.00 1974-1978 Mustang II 8"
57.25 1957-1959 Ford, Ranchero, station wagon
57.25 1965-1966 Mustang
58.00 1966-1977 Bronco
58.00 1964-1965 Falcon
58.00 1977-1981 Granada/Versailles
58.50 1977-1981 Versailles
59.25 1967-1970 Mustang, Fairlane, Comet, Cougar
60.00 1967 Cougar
60.00 1958-1960 Edsel
61.00 1964-1971 Ford full size
61.00 1949-1951 Mercury
61.25 1957-1972 Ford F-100 pickup
61.25 1960-1964 Ford full size
61.25 1971-1973 Mustang
61.25 1967-1973 Torino, Ranchero, Fairlane
63.00 1970-1979 Ranchero & Torino
63.00 1972-1979 Ford full size & intermediate
63.50 1967 Fairlane (coil springs)
65.25 1973-1986 Ford F-150 pickup
65.25 1978-1986 Bronco
65.25 1973-1986 Ford van 3/4 ton
68.00 1972 Ford van 3/4 ton
69.25 1977-1986 Ford E-150 van

Mopar
Outside Width (in.) Year Model
55.60 1960-1976 7-1/4" A-body
55.60 1973-1976 8-1/4" A-body
55.60 1966-1972 8-3/4" A-body
55.60 All 8-3/4" A-body
56.00 1932-1934 All
57.40 1963-1972 7-1/4" A-body
58.54 All 8-1/4" F-body
58.54 All 8-1/4" M-body
58.54 All 8-1/4" J-body
59.00 1935-1936 All
59.14 1966-1970 9-3/4" B-body
59.20 1962-1970 8-3/4" B-body
60.00 1937-1948 All
60.70 All 8-3/4" E-body
60.70 All 9-3/4" E-body
62.00 All 8-1/4" B-body
62.00 1971-1974 8-3/4" B-body
62.00 All 9-1/4" B-body
63.40 All 8-1/4" C-body
63.40 1971-1974 8-3/4" B-body S.W.
63.40 All 9-1/4" C-body

Axle to axle, rear differential
GM car
  • 58.0" -- 1978-'88 mid size GM car, Malibu, Monte Carlo (1982-up metric studs), Regal with 10-bolt diff, 1965-'67 Nova
  • 59.0" -- 1968-'83 Corvette
  • 60.0" -- 1955-'64 Chevy, 1967-'69 Camaro, 1964-'67 Chevelle, 1968-'74 Nova, 1984-'95 Corvette
  • 62.0" -- 1989 Trans Am
GM truck
  • 60.5" -- 1964-'69 1/2 ton 2WD Chevy, some GMC 6 lug rear end 12 bolt coil spring set-up
Ford car
  • 56.5" -- 1971-'77 Ford Maverick w/8" diff
  • 57.0" -- 1971-'74 V8 Maverick w/8" diff, all 1975-'77 6 and 8 cylinder engines, Maverick 5 lug w/8" diff, 1949-'51 Ford, 1957-'59 Ford w/9" diff
  • 57.25" -- 1964-1/2-'65 Mustang
  • 58.0" -- 1980 Granada/Lincoln Versailles, 1967-'70 Mustang/Cougar/Fairlane
  • 58.5" -- Granada (year unknown)
  • 59.5" -- 1940 Ford
  • 60.0" -- 1971-'73 Mustang/Cougar
  • 62.0" -- 1973-'76 Torino
Additional specifications
Rear axle widths
These dimensions do not include brake drums and are measured from backing plate to backing plate. Actual wheel track could be as much as 6" to 8"depending on drum size:

  • 46" to 47"
    • '66 to '77 Bronco
  • 48" to 49"
    • '72 to '75 Datsun pickup
    • '71 Dodge Colt
    • '72 to '73 Mazda
  • 50" to 51"
    • '73 to '76 A-Body Mopar
    • '65 AMC American
    • '58 to '60 Thunderbird
  • 52" to 53"
    • '28 to '40 Ford
    • '57-'59 Ford and Edsel
    • '63-'69 Falcon/Comet
    • '63 to '65 Fairlane
    • '65 to '66 Mustang
    • '62 Buick Skylark
    • '67 to '70 Mustang/Cougar 6 cyl.
    • '71 to '74 Maverick/Comet
    • '71 to '72 Pinto
    • '68 to '69 AMX and Javelin
    • '63-'72 A-Body Mopar except 8 ¾" axle
    • '75 to '79 Granada/Monarch
  • 54" to 55"
    • '39 to '48 Chevrolet
    • '41 to '48 Ford
    • '55 to '57 Chevrolet
    • '68 to '69 Fairlane
    • '67 to '70 Mustang/Cougar 8 cyl.
    • '62 to '70 B-body Mopar w/ 8 ¾" or 9 ¾" axle
    • '79 to'85 Toyota pickup
    • '68 to '72 Chevelle
    • '74 to '79 Mustang II/Pinto/Capri/Bobcat
  • 56" to 57"
    • '70 to '71 Torino/Cyclone
    • '71 to '73 Mustang/Cougar
    • '60 to '64 Ford full-size
    • '61 to '67 Thunderbird
    • '58 to '72 Ford F-100 pickup
    • '26 to '39 Plymouth/Dodge
    • '67 Lincoln
    • '69 Dodge Van
    • '54 to '56 Ford pickup
    • '26 to '46 Chevy truck
    • '25 to '39 Chevrolet cars
    • '28 to '34 Ford cars and pickups
    • '49 to '56 Ford/Mercury car
    • '71 to '74 B-body and E-Body Mopar
    • '63 to '70 Chrysler C-body cars
    • '75 to '78 Maverick/Comet
    • '75 to '76 Dart
  • 58" to 59"
    • '61 Pontiac 57-7/8" actual
    • '73 to '90 Ford F-100/150 pickup
    • '61 Chevrolet full-size
    • '65 Cadillac
    • '66 Buick full-size
    • '66 to '67 Chevrolet full-size
    • '69 Oldsmobile full-size
    • '72 to '73 Torino
    • '40 to '54 Chevy cars
    • '35 to '48 Ford
    • '35 to '41 Ford pickup
    • '55 to '59 Chevy pickup
    • '71 to '74 B-body station wagon
    • '71 to '74 Chrysler C-body cars
    • '86 to '95 Toyota pickup
    • '78 to '86 Monte Carlo/Century
    • '68 to '83 Corvette
    • '68 to '74 Apollo
    • '78 to '86 Grand Prix
    • '76 to '80 Scout with 9" axle
    • '78 to '80 Bronco with 9" axle
  • 60" to 61"
    • '40 to '52 Plymouth/Dodge
    • '26 to '39 Chrysler/Desoto
    • '47 to '55 Chevy pickup
    • '70 to '72 Lincoln Continental
    • '68 to '74 Nova/GTO
    • '76 to '80 Camaro and Firebird
    • '84 to '95 Corvette
    • '76 to '80 Aspen and Volare
    • '74 to '77 Jeep pickup
These measurements are from brake drum to brake drum (WMS-WMS):
  • 56-1/2"
    • '74 Maverick
  • 57"
    • '75 Mustang II
  • 57-1/4"
    • '65 to '66 Mustang
    • '57-'64 Ford full-size
    • '57 to '59 Ranchero and station wagon
  • 58"
    • '66 to '77 Bronco
    • '64 Falcon
  • 58-1/2"
    • '77 to '81 Granada and Lincoln Versailles
  • 59-1/4"
    • '67 to '70 Mustang
    • '67 to '71 Comet, Cougar, Fairlane
  • 60"
    • '67 Cougar
  • 60.5"
    • '97-06 Jeep TJ/LJ
  • 61-1/4"
    • '71 to '73 Mustang
    • '67 to '73 Torino/Ranchero with 9 ¼" axle
  • 63-1/2"
    • '67 Fairlane with coil springs
  • 65-1/4"
    • '73 to '86 Ford ¾ ton Van
  • 65-3/8
    • '07-17 Jeep JK/JKU
  • 68"
    • '72 Ford ¾ ton Van
 
Last edited:
https://m.roadkillcustoms.com/rear-end-widths-classic-american-cars/

https://www.quickperformance.com/Suspension-Measurements_ep_44.html


scheppja
07-14-2014, 04:56 PM
In searching the web I found the following links that have a massive of information on rear end widths and wanted to share.

http://www.carnut.com/specs/rear.html

http://www.crankshaftcoalition.com/wiki/Wheelbase,_track_width,_and_differential_measureme nts

differentials / axles

https://www.currieenterprises.com/o...MIt5jQ8YDg4wIVAZyzCh3CMwtCEAAYAiAAEgJrkfD_BwE

https://www.markwilliams.com/axles....MIt5jQ8YDg4wIVAZyzCh3CMwtCEAAYASAAEgImPvD_BwE

https://www.moserengineering.com/

https://www.vividracing.com/axles-c-5892.html

https://www.driveshaftshop.com/our-axle-system

https://www.strangeengineering.net/

http://www.gatorracingaxles.com/

https://www.raxles.com/highperformance.aspx

https://www.quickperformance.com/Fo...MIt5jQ8YDg4wIVAZyzCh3CMwtCEAMYAiAAEgJKBfD_BwE

The information below is from crankshaftcoalition.com

Note: All measurements are in inches unless otherwise noted.
This article will be divided into at least three sections

The first section will list wheelbase, front track and rear track of vehicles in inches, so that those interested in frame swaps or clip swaps can find the correct donor vehicle. Dimensions will be listed left to right as wb/ft/rt followed by the year, make and model of the vehicle. For instance: 86.0, 50.6, 50.3 -- 1952 Morris Minor. If one or more of the dimensions are unknown, NA should be inserted in that space. For instance, if the wheelbase of the Morris were unknown, it would be listed as NA, 50.6, 50.3 -- 1952 Morris Minor. If the wheelbase were known, but the front and rear track were unknown, it would be listed as 86.0, NA, NA -- 1952 Morris Minor.
Guide for taking measurementsMost often, wheelbase is the dimension from the center point at the end of the front axle or spindle to the center point of the end of the rear axle. Note that the measurement could also be described as being between the center points of the circles described by the front and rear wheels on the same side of the vehicle.

Track is the dimension from the centerline of the tire tread on one tire to the centerline of the tire tread on the opposite tire on the same end of the vehicle. E.G.: Front track or rear track. On vehicles with dual wheels, that measurement is commonly taken from halfway between the centers of each tire on both right and left sides. There are also "Inner track" and "Outer track" dimensions, measured from the center lines of the inner tires and the outer tires of the dual wheel axle.

The second section will be listed as axle flange to axle flange where the wheel bolts on. Drum to drum would be close enough to the same if that's all the information you have to post. The only difference between the two would be the thickness of the material of the two drums or brake rotors/discs at the studs.

The third section will list backing plate to backing plate on the rear differential. This information will require knowing the width of the brake drum to determine flange to flange dimensions. Find brake drum width, multiply X two and add that figure to the plate to plate dimension to get flange to flange.

Wheelbase, front track, rear track

American Motors
100.0, 61.2, 60.2 -- 1975 AMC Pacer

GM car
122.0, 58.31,59.25 - 1937 Buick Special
126.0, 58.31,59.25 - 1937 Buick Century
N/A,,, 59.1, 58.8 -- 1968-'74 Buick Apollo
112.0 coupe; 116.0 sedan,wagon; 61.5, 60.7 -- 1973-'77 Buick Regal
111.0, 59.1, 59.7 -- 1975 Buick Skylark
N/A,,, 59.0, 58.8 -- 1978-'86 Buick Century
115, 56.69, 58.75 -- 1949-'54 Chevy & Canadian Pontiac
115.0, 58.5, 60.0 -- 1955-'57 Chevy
108.1, 58.7, 60.5 -- 1967-'69 Chevy Camaro (other source shows 108.1/59.0/58.9)
108.1, 60.4, 61.0 -- 1970 Chevy Camaro
108.1, 58.9, 59.5 -- 1970-'73 Chevy Camaro Z-28
N/A,,, 61.3, 60.5 -- 1976-'80 Chevy Camaro Z-28, Pontiac Trans Am
101.1, 60.7, N/A, -- 1993-'02 Chevy Camaro
101.0, 60.7, 60.6 -- 1986 Chevy Camaro IROC Z
101.1, 60.7, 60.7 -- 1998 Chevy Camaro
112.3, 63.7, 64.1 -- 1999 Chevy Camaro LS, LT
112.3, 63.7, 63.7 -- 1999 Chevy Camaro SS
119.0, 62.5, 62.4 -- 1965-'70 Chevy Caprice
121.5, N/A,,, N/A -- 1971-'76 Chevy Caprice coupe/sedan
125.0, N/A,, 64.5 -- 1971-'76 Chevy Caprice station wagon
116.0, N/A,,, N/A -- 1977-'90 Chevy Caprice
115.9, 61.8, 60.7 -- 1991-'96 Chevy Caprice
112.0 coupe; 116.0 sedan,wagon, 61.5, 60.7 -- 1973-'77 Chevy Malibu, Laguna
102.0, 57.0, 59.0 -- 1954-'62 Chevy Corvette
N/A,,, 58.7, 59.5 -- 1968-'82 Chevy Corvette
N/A,,, 59.6, 60.4 -- 1984-'95 Chevy Corvette
108.0, 58.5, 58.8 -- 1978-'88 Chevy Monte Carlo, Malibu, El Camino (117.1 wheelbase), Olds Cutlass, Pontiac Grand Prix
111.0, 59.8, 59.6 -- 1968-'74 Chevy Nova
97.0, 54.7,, 53.6 -- 1971-'77 Chevy Vega, 1973-'77 Pontiac Astre, 1975-'80 Chevy Monza, Buick Skyhawk, Olds Starfire, 1976-'80 Pontiac Sunbird
112.0 coupe; 116.0 sedan,wagon, 61.5, 60.7 -- 1973-'77 Oldsmobile Cutlass, 442
112.0 coupe; 116.0 sedan,wagon, 61.5, 60.7 -- 1973-'77 Pontiac Grand Prix, LeMans
N/A,,, 58.9, 59.0 -- 1978-'86 Pontiac Grand Prix
115.0, N/A,,, N/A -- 1966 Pontiac GTO
N/A,,, 59.9, 59.6 -- 1968-'74 Pontiac GTO
112.25, 57.5, 59.0 -- 1939-'40 Chevy w/knee action shocks
112.25, 56.375, 59 -- 1939 Chevy w/I-beam front end
116.0, 57.6, 60.0 -- 1941-'48 Chevy

GM truck
106.5, 64.5, 63.0 -- 1973-'91 Chevy Blazer 2WD
106.5, 65.75, 62.75-- 1973-'91 Chevy Blazer 4WD
131.5, 65.8, 62.7 -- 1973-'87 Chevy C-10, K-10
131.5, 65.8, 62.7 -- 1973-'87 Chevy C-20, K-20, C30
164.5, 65.8, 62.7 -- 1973-'91 Chevy C-30 Crew Cab
129.5, 65.8, 62.7 -- 1973-'91 Chevy Suburban
114.5, 60.52,61.02 -- 1955 Chevy 2nd. series (1955 1st. series was same as 1954)
116.0, 59.5, 60,, -- 1947-'54 Chevy AD 1/2 ton
125.25,N/A,,,,62,, -- 1947-'54 Chevy AD 3/4 ton
137.0, N/A,,, N/A,, -- 1947-'54 Chevy AD 1 ton
144.0, N/A,,, N/A,, -- 1902 Chevy Silverado 1500 4WD
102.4, N/A,,, N/A,, -- 1972-'80 Chevy LUV w/standard cab and 73.1" box (unequal length A-arms with torsion bars was standard front suspension on LUV)
104.3, N/A,,, 54",, -- 1981-'82 Chevy LUV w/standard cab and 73.1" box (unequal length A-arms with torsion bars was standard front suspension on LUV)
117.9, N/A,,, 54",, -- 1978-'82 Chevy LUV w/standard cab and 90.1" box (unequal length A-arms with torsion bars was standard front suspension on LUV)
100.5, 54.5, 54.7 -- 1983-'01 Chevy S-10 Blazer 2-dr., 1983-'01 GMC Jimmy 2-dr.
107.0, 54.5, 54.7 -- 1990-'01 Chevy S-10 Blazer 4-dr., 1990-'01 GMC Jimmy 4-dr.
108.3, 54.5, 54.7 -- 1982-'93 Chevy S-10 standard cab, 73" box, 1982-'93 GMC reg cab, 73" box (stock Malibu and El Camino spindles are bolt-on)
117.9, 54.5, 54.7 -- 1982-'93 Chevy S-10 standard cab, 89" box, '82-'93 GMC regular cab, 89" box
122.9, 54.5, 54.7 -- 1983-? Chevy S-10 extended cab, '83-? GMC Sanoma extended cab
135.0, 67.8, 67.8 -- 1908 Chevy Express Cargo 1500 work van
111.2, n/a, n/a, -- 1904 - '12 Chevy Colorado reg. cab
126 , n/a, n/a, -- 1904 - '12 Chevy Colorado ext. cab

Ford car
108, N/A,,, N/A -- 1964-'68 Mustang
96.2, 55.6, 55.8 -- 1974-'79 Ford Mustang II, Ford Pinto, Mercury Bobcat, Mercury Capri (track also listed as 55.1/55.3)
100.5, 56.6, 57.0 -- 1986 Ford Mustang GT

Ford truck 1953-'55
F100 1/2-ton - 110"
F250 3/4-ton - 118"
F350 3/4-ton - 130" (F350 was still classified as 3/4 ton trucks through '55)

1956-'60
F100 1/2-ton SWB - 110"
F100 1/2-ton LWB - 118"
F250 3/4-ton - 118"
F350 1-ton - 130"

1961-'63
F100 1/2-ton SWB - 114"
F100 1/2-ton LWB - 122"
F250 3/4-ton - 122"
F350 1-ton - 132"

1964
F100 1/2-ton SWB - 114"
F100 1/2-ton LWB - 128"
F250 3/4-ton - 128"
F350 1-ton - 132"

1965-'66
F100 1/2-ton SWB - 115"
F100 1/2-ton LWB - 129"
F250 3/4-ton - 129"
F250 3/4-ton Crew Cab - 147"
F350 1-ton - 132"
F350 1-ton Crew Cab - 152"

1967-'68
F100 1/2-ton SWB - 115"
F100 1/2-ton LWB - 131"
F250 3/4-ton - 131"
F250 3/4-ton Crew Cab - 147"
F350 1-ton - 132"
F350 1-ton Crew Cab - 152"

1969-'70
F100 1/2-ton SWB - 115"
F100 1/2-ton LWB - 131"
F250 3/4-ton - 131"
F250 3/4-ton Crew Cab - 147"
F350 1-ton - 135"
F350 1-ton Crew Cab - 159.5"

1971
F100 1/2-ton SWB - 115"
F100 1/2-ton LWB - 131"
F250 3/4-ton - 131"
F250 3/4-ton Crew Cab - 159"
F350 1-ton - 135"
F350 1-ton Crew Cab - 159.5"

1972
F100 1/2-ton SWB - 115"
F100 1/2-ton LWB - 131"
F250 3/4-ton - 131"
F250 3/4-ton Crew Cab - 159"
F350 1-ton - 135"
F350 1-ton Crew Cab - 159"

1973
F100 1/2-ton SWB - 117"
F100 1/2-ton LWB - 133"
F250 3/4-ton - 133"
F250 3/4-ton Crew Cab - 161"
F350 1-ton - 137"
F350 1-ton Crew Cab - 165.5"

1974
F100 1/2-ton SWB - 117"
F100 1/2-ton LWB - 133"
F100 1/2-ton SuperCab LWB 6-ft. bed - 140"
F100 1/2-ton SuperCab LWB 8-ft. bed - 155"
F250 3/4-ton - 133"
F250 3/4-ton SuperCab - 140"
F250 3/4-ton Crew Cab - 155"
F350 1-ton - 137"
F350 1-ton SuperCab - 140"
F350 1-ton Platform/Stake - 161"
F350 1-ton Crew Cab - 166.5"

1975
F100 1/2-ton SWB - 117"
F100 1/2-ton LWB - 133"
F100 1/2-ton SuperCab 6-ft. bed - 140"
F100 1/2-ton SuperCab 8-ft. bed - 155"
F150 1/2-ton - 133"
F250 3/4-ton - 133"
F250 3/4-ton Crew Cab - 155"
F350 1-ton - 137"
F350 1-ton Platform/Stake - 161"
F350 1-ton SuperCab - 155"
F350 1-ton Crew Cab - 166.5"

1976
F100 1/2-ton SWB - 117"
F100 1/2-ton LWB - 133"
F100 1/2-ton SuperCab - 155"
F150 1/2-ton - 133"
F250 3/4-ton - 133"
F250 3/4-ton Crew Cab - 155"
F350 1-ton - 137"
F350 1-ton SuperCab - 155"
F350 1-ton Crew Cab - 166.5"

1977
F100 1/2-ton SWB - 117"
F100 1/2-ton LWB - 133"
F100 1/2-ton SuperCab - 155"
F150 1/2-ton - 133"
F150 SuperCab - 155"
F250 3/4-ton - 133"
F250 3/4-ton Crew Cab - 155"
F350 1-ton - 137"
F350 1-ton SuperCab - 155"
F350 1-ton Crew Cab - 166.5"

1978-'79
F100 1/2-ton SWB - 117"
F100 1/2-ton LWB - 133"
F100 1/2-ton SuperCab - 155"
F150 1/2-ton - 133"
F150 SuperCab - 155"
F250 3/4-ton - 133"
F250 3/4-ton SuperCab - 155"
F250 3/4-ton Crew Cab - 155"
F350 1-ton Camper Special- 140"
F350 1-ton SuperCab - 155"
F350 1-ton Crew Cab - 166.5"

MOPAR car
115.0, 61.9, 62.0 -- 1975 Chrysler Cordoba
NA,,,, 58.9, 59.0 -- 1975-'79 Dodge Aspen, Plymouth Volare
111.0, 59.2, 55.6 -- 1967-'76 Dodge Dart, Plymouth Scamp
108.0, 59.2, 55.6 -- 1970-'76 Dodge Demon/Dart Sport, Plymouth Duster

Miscellaneous
105.0, 58.0, 58.0 -- 1951 Cunningham C-1, C-2R
107.0, 58.0, 58.0 -- 1953 Cunningham C-3
100.0, 54.0, 54.0 -- 1952 Cunningham C-4R, C-4RK
100.0, 55.0, 55.0 -- 1953 Cunningham C-5R
100.0, 52.0, 52.0 -- 1955 Cunningham C-6R
086.0, 50.5, 50.3 -- 1948-'74 Morris Minor

Rearend widths

Chevrolet Outside Width Year Model
57.75 1962-1964 Chevy II/Nova
57.75 1965-1967 Chevy II/Nova
58.00 1978-1988 Chevy Malibu, Monte Carlo
59.50 1968-1982 Corvette
60.00 1955-1964 Chevy car
60.00 1967-1969 Camaro
60.25 1968-1979 Chevy II/Nova
60.50 1984-1995 Corvette
60.50 1964-1967 Chevelle
62.00 1955-1959 Chevy pickup
62.50 1968-1972 Chevelle
61.00 1970-1981 Camaro/Firebird

Ford Outside Width Year Model
56.50 1969-1977 Maverick 8"
57.00 1974-1978 Mustang II 8"
57.25 1957-1959 Ford, Ranchero, station wagon
57.25 1965-1966 Mustang
58.00 1966-1977 Bronco
58.00 1964-1965 Falcon
58.00 1977-1981 Granada/Versailles
58.50 1977-1981 Versailles
59.25 1967-1970 Mustang, Fairlane, Comet, Cougar
60.00 1967 Cougar
60.00 1958-1960 Edsel
61.00 1964-1971 Ford full size
61.00 1949-1951 Mercury
61.25 1957-1972 Ford F-100 pickup
61.25 1960-1964 Ford full size
61.25 1971-1973 Mustang
61.25 1967-1973 Torino, Ranchero, Fairlane
63.00 1970-1979 Ranchero & Torino
63.00 1972-1979 Ford full size & intermediate
63.50 1967 Fairlane (coil springs)
65.25 1973-1986 Ford F-150 pickup
65.25 1978-1986 Bronco
65.25 1973-1986 Ford van 3/4 ton
68.00 1972 Ford van 3/4 ton
69.25 1977-1986 Ford E-150 van

MOPAR Outside Width Year Model
55.60 1960-1976 7 1/4 A-body
55.60 1973-1976 8 1/4 A-body
55.60 1966-1972 8 3/4 A-body
55.60 All 8 3/4 A-body
56.00 1932-1934 All Mopars
57.40 1963-1972 7 1/4 A-body
58.54 All 8 1/4 F-body
58.54 All 8 1/4 M-body
58.54 All 8 1/4 J-body
59.00 1935-1936 All Mopars
59.14 1966-1970 9 3/4 B-body
59.20 1962-1970 8 3/4 B-body
60.00 1937-1948 All Mopars
60.70 All 8 3/4 E-body
60.70 All 9 3/4 E-body
62.00 All 8 1/4 B-body
62.00 1971-1974 8 3/4 B-body
62.00 All 9 1/4 B-body
63.40 All 8 1/4 C-body
63.40 1971-1974 8 3/4 B-body S.W.
63.40 All 9 1/4 C-body

Axle to axle, rear differential GM car
58.0 -- 1978-'88 mid size GM car, Malibu, Monte Carlo (1982-up metric studs), Regal with 10-bolt diff, 1965-'67 Nova
59.0 -- 1968-'83 Corvette
60.0 -- 1955-'64 Chevy, 1967-'69 Camaro, 1964-'67 Chevelle, 1968-'74 Nova, 1984-'95 Corvette
62.0 -- 1989 Trans Am

GM truck
60.5 -- 1964-'69 1/2 ton 2WD Chevy, Some GMC 6 lug rear end 12 bolt coil spring set-up

Ford car
56.5 -- 1971-'77 Ford Maverick w/8" diff
57.0 -- 1971-'74 V8 Maverick w/8" diff, all 1975-'77 6 and 8 cylinder engines, Maverick 5 lug w/8" diff, 1949-'51 Ford, 1957-'59 Ford w/9" diff
57.25 -- 1964-1/2-'65 Mustang
58.0 -- 1980 Granada/Lincoln Versailles, 1967-'70 Mustang/Cougar/Fairlane
58.5 -- Granada (year unknown)
59.5 -- 1940 Ford
60.0 -- 1971-'73 Mustang/Cougar
62.0 -- 1973-'76 Torino


Representative for comparison purposes only
Ford

Outside
Width
Year Model
56.50 1969-1977 Maverick 8"
56.50 1990-1992 Ford Ranger 8.8"
56.75 1995-2003 Ford Explorer 8.8" Narrowed w/2 short side axles
57.00 1974-1978 Mustang II 8"
57.25 1957-1959 Ford, Ranchero, Station Wagon
57.25 1965-1966 Mustang
58.00 1966-1977 Bronco
58.00 1964-1965 Falcon
58.00 1977-1981 Granada/Versailles
58.50 1977-1981 Versailles
58.50 1993-2009 Ford Ranger 8.8"
59.25 1967-1970 Mustang, Fairlane, Comet, Cougar
59.81 1995-2003 Ford Explorer 8.8" 31 Spline Disc Brake
60.00 1967 Cougar
60.00 1958-1960 Edsel
61.00 1964-1971 Ford Full Size
61.00 1949-1951 Mercury
61.25 1957-1972 Ford F-100 Pickup
61.25 1960-1964 Ford Full Size
61.25 1971-1973 Mustang
61.25 1967-1973 Torino, Ranchero, Fairlane
63.00 1970-1979 Ranchero & Torino
63.00 1972-1979 Ford Full Size & Intermediate
63.50 1967 Fairlane (Coil Springs)
65.25 1973-1986 Ford F-150 Pickup
65.25 1978-1986 Bronco
65.25 1973-1986 Ford Van 3/4 Ton
68.00 1972 Ford Van 3/4 Ton
69.25 1977-1986 Ford E-150 Van


Chevy

Outside
Width
Year Model
54.25 1983-2004 Chevy S10 2WD, GMC S15 2WD
57.75 1962-1964 Chevy II/Nova
57.75 1965-1967 Chevy II/Nova
58.00 1978-1988 Chevy Malibu, Monte Carlo
59.50 1968-1982 Corvette
60.00 1955-1964 Chevy Car
60.00 1967-1969 Camaro
60.25 1968-1979 Chevy II/Nova
60.50 1984-1995 Corvette
60.50 1964-1967 Chevelle
62.00 1955-1959 Chevy Pickup
62.50 1968-1972 Chevelle
62.50 1970-1981 Camaro/Firebird
Mopar

Outside
Width
Year Model
55.60 1960-1976 7 1/4 A-body
55.60 1973-1976 8 1/4 A-body
55.60 1966-1972 8 3/4 A-body
55.60 All 8 3/4 A-body
56.00 1932-1934 All Mopars
57.40 1963-1972 7 1/4 A-body
58.54 All 8 1/4 F-body
58.54 All 8 1/4 M-body
58.54 All 8 1/4 J-body
59.00 1935-1936 All Mopars
59.14 1966-1970 9 3/4 B-body
59.20 1962-1970 8 3/4 B-body
60.00 1937-1948 All Mopars
60.70 All 8 3/4 E-body
60.70 All 9 3/4 E-body
62.00 All 8 1/4 B-body
62.00 1971-1974 8 3/4 B-body
62.00 All 9 1/4 B-body
63.40 All 8 1/4 C-body
63.40 1971-1974 8 3/4 B-body S.W.
63.40 All 9 1/4 C-body
 
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The gear ratio in an axle determines how many times the drive shaft needs to spin in order to turn the wheels one rotation. For example, a 3.73 gear ratio requires the drive shaft to spin 3.73 times to turn the tires around once.
In the diagram below, the drive shaft turns the pinion against the ring gear that is connected to the wheels via the axle shafts. The number of teeth on the pinion and the ring gear are what determine the gear ratio.

https://www.chevyhardcore.com/tech-stories/drivetrain/12-bolt-rearend-guide/


differential.jpg


The higher a gear ratio is numerically, the more the engine needs to turn to spin the tires. Higher gear ratios work great for trucks that need more torque to get heavy loads moving while numerically lower gears are better for racing and for improving highway gas mileage because the engine can turn slower at higher speeds.


Find the correct gear ratio for your vehicle
with our Gear Ratio Finder


Calculate your existing gear ratio
with out Gear Ratio Calculator




NEW! - Need Help with Carrier Breaks and Thick Gears? Check out the new comments section below!




Ring and Pinion Gear Sizes and Alignment
The gear ratio of any axle can be calculated by dividing the number of teeth on the ring gear by the number of teeth on the pinion gear. For example, an axle with 41 ring gear teeth and 11 pinion gear teeth would have a 3.73 gear ratio (41/11 =3.73).

Low gear sets have more teeth on the pinion gear than high ratio gears do and as such the overall diameter of the pinion gear tends to change significantly across the scale of ratios. Ring gears, on the other hand, maintain their size because the teeth are cut on the face of the gear and not along the circumference. As a result, and because axle housings are machined with a fixed position for the pinion and differential carrier that holds the ring gear, a gap is created between the two gears as the gear ratio increases.

thick_gears_2.jpg

The gap between the ring gear and pinion gear is corrected in two ways: The first way is to make the ring gear thicker and the other is to use an offset differential carrier that moves the ring gear closer to the pinion. While it would be nice to avoid changing the carrier and use thicker gears for all ratios, there is a point at which the rotating mass of the additional material begins to negatively affect performance. This is why many axle manufacturers use two different carriers for high and low gear ratios.

thick_gears_3.jpg



What is a Carrier Break?
Axles that are designed for use with a large range of gear ratios often have two different differential carriers, one for lower gears and one for higher gears. The point at which the axle switches from one carrier to the other is called the carrier break. For example, the Dana 60 axle has a 4.10/4.56 carrier break that requires one carrier for 4.10 and numerically lower gears and another carrier for 4.56 and higher gears.

When changing gears in an axle, it is important to determine if the axle has a carrier break and if so, which carrier it has installed. If the axle does not have a carrier break, then any aftermarket gears will fit just fine. If the axle does use a carrier break, then the first thing that needs to be checked is if the new gear ratio is on the same side of the carrier break as the existing gears or if they will be "jumping the break".

For gear changes where the gear ratio crosses the carrier break, the installation will require the use of the other differential carrier. Luckily, aftermarket differential and locker manufacturers are aware of this and almost always offer models for both lower and higher carriers.

Some aftermarket gear manufacturers also offer ring gear spacers and thick gears that are designed to jump a carrier break without the need for changing the carrier. These gears are not available for all applications or all gear ratios, however, whenever possible, they are a great option.







How to Select The Right Gears and Carrier
Step 1: Determine If Your Axle Has A Carrier Break
Find your axle in the table below to see if it has a carrier break. If so, then you need to check and see if your current gear ratio is on the low carrier or the high carrier. If not, then all gear ratios will fit on the stock carrier and you can't go wrong.

Step 2: Find Your Existing Gear Ratio
If you don't know your existing gear ratio, you can use our Gear Ratio Calculator to figure that out.

Step 3: Select Your New Gear Ratio
Using our Gear Ratio Finder and Engine RPM Calculator, select the appropriate gear ratio for your application.

Step 4: Check If The New Gears Jump the Carrier Break
If your new gear ratio is within the same carrier range as the stock gears, then standard gears will work fine. If your current gear ratio is on the low carrier and your new gears are on the high carrier, then you will need to change the carrier, use a ring gear spacer, or find thick gears. If your existing gears are on the high carrier, and your new gears require the lower carrier, then you will need to change to the lower carrier.

Current Ratio New Ratio Installation Options
Lower Carrier Lower Carrier Standard Gears on Lower Carrier
Lower Carrier Higher Carrier Standard Gears on Lower Carrier with Ring Gear Spacer
Standard Gears on Higher Carrier
Thick Gears on Lower Carrier
Higher Carrier Lower Carrier Standard Gears on Lower Carrier
Higher Carrier Higher Carrier Standard Gears on Higher Carrier

Tip: Aftermarket Carriers, Limited Slips, and Lockers
Most aftermarket differential manufacturers offer both carriers so if you plan on upgrading your differential with your new gears, make sure that you order the correct one so that you can run standard gears and avoid needing thick gears or spacers.







Popular Axle Carrier Breaks
Axle Low Carrier High Carrier
AAM 9.25" All / No Break Same
AAM 9.25" IFS All / No Break Same
AAM 10.5" All / No Break Same
AAM 11.5" All / No Break Same
AMC Model 20 2.73 & Down 3.08 & Up
AMC Model 35 3.31 & Down 3.54 & Up
Chrysler 7.25" 2.47 & Down 2.76 & Up
Chrysler 8.25" 2.47 & Down 2.76 & Up
Chrysler 8.75" (All) All / No Break Same
Chrysler 9.25" All / No Break Same
Chrysler 10.5" All / No Break Same
Chrysler 11.5" All / No Break Same
Dana 27 3.73 & Down 3.92 & Up
Dana 30 3.54 & Down 3.73 & Up
Dana 35 3.31 & Down 3.54 & Up
Dana 36 ICA 2.73 & Down 3.07 & Up
Dana 44 3.73 & Down 3.92 & Up
Dana 50 All / No Break Same
Dana 60 4.10 & Down 4.56 & Up
Dana 61 All / No Break Same
Dana 70 4.10 & Down 4.56 & Up
Dana 80 3.73 & Down 4.10 & Up
Ford 7.5" All / No Break Same
Ford 8" All / No Break Same
Ford 8.8" All / No Break Same
Ford 9 Inch All / No Break Same
Ford 9.75" All / No Break Same
Ford 10.25" / 10.5" All / No Break Same

Axle Low Carrier High Carrier
GM 7.2" IFS 3.08 & Down 3.42 & Up
GM 7.5" / 7.6" 3.08 & Down 3.23 & Up
GM 8.0" 3.08 & Down 3.31 & Up
GM 8.2" 2.76 & Down 3.07 & Up
GM 8.2" BOP 2.76 & Down / 2.94 to 3.23 / 3.31 & Up
GM 8.25" IFS All / No Break Same
GM 8.5" / 8.6" 2.56 & Down 2.73 & Up
GM 9.25" IFS All / No Break Same
GM 9.5" All / No Break Same
GM 10.5" 14 Bolt 4.10 & Down 4.56 & Up
GM 11.5" All / No Break Same
GM 55P / 55T All / No Break Same
GM 12 Bolt Car 2.76 & Down / 3.07 to 3.90 / 4.10 & Up
GM 12 Bolt Truck 2.73 & Down / 2.76 to 3.42 / 3.73 & Up
Suzuki Samurai All / No Break Same
Toyota 7.5" All / No Break Same
Toyota 8" (4Cyl) All / No Break Same
Toyota 8" TV6 All / No Break Same
Toyota T100 All / No Break Same
Toyota 9.5" All / No Break Same
Toyota 10.5" All / No Break Same
Land Cruiser 8" All / No Break Same
Land Cruiser 9.5" All / No Break Same

Axle Carrier Break data is ©Copyright Crawlpedia.com -
 
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Hi guys, trying to remove the cross shaft in the 12 bolt diff. The locating bolt has sheared & the cross shaft has spun in the housing. One of the side gears has also worn badly on the shaft.
end result - the shaft will not come out. The shaft is hard, so can't cut / drill.
What would you do?

WATCHING ALL these videos may help






 





if you trashed the 12 bolt internals and can,t get the cross pin out,
you can always pull the axles after using a cut off wheel on a die grinder to cut out the center section of the cross shaft ,
so the axles and c clips can be removed so the posi-unit and gears can be removed ,
so you can clean and reinstall the center section area and posi after a rebuild
its very slow and messy work,
but it can be done (yeah don,t ask) how I know,
trust me, a SERIOUS big block I built with 13.7:1 compression and using 13" wide 30" tall slicks and a couple hundred hard launches,
will trash a 12 bolt even with aftermarket axles and 4.88 gears

and yeah the spider gears were already trashed so they were also cut out in both my cases,
and its one reason I vastly prefer using a dana 60 in any serious performance car, as I trashed a few 12 bolts racing before I swapped to dana 60 differentials
https://www.harborfreight.com/pneum...al-die-grinder-with-4-in-extension-64624.html
and before some one says you can,t fit that size slick on that 1965 le mans car...
remember with the car I raced , we did the mods required,I learned to weld in college
as an engineer and machinist student,
that race car was how I learned a few more skills in metal fabrication and sheet metal welding ,
AIR SHOCKS, building a TUBED REAR DIFFERENTIAL AREA, added a fuel cell,
swapped tpp disc brakes on the rear differential,
and yes I hung out with and I knew how too both find experienced racers ,
both circle track and drag racers, and several dealer ship mechanics
willing to help and work with me, and learned how to do the required body and fender mods
and I also did similar mods on a 1969 camaro and my 1968 corvette

http://garage.grumpysperformance.co...-resulting-from-an-engine-swap.898/#post-3239
 
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