swap info guide

Discussion in 'MISC. mods and equip.' started by Grumpy, May 30, 2018.

  1. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member


    Chevrolet Transmission Swap Guide - Swap Into Overdrive
    A Transmission Swapping Guide for Early Chevrolets
    Mike Petralia Sep 1, 1999
    Overdrive is king of cruise, and GM has done its part to engineer strong, reliable overdrive automatic and manual transmissions for all its new cars. This is the venerable TH700-R4/4L60 manufactured by JET Performance specifically for swapping into early Chevy iron.

    This is the aftermarket T56 six-speed manual trans available from National Drivetrain. The unit is built by Borg-Warner to handle up to 450 lb-ft of torque and works with a mechanical speedo drive. It is a direct replacement for the weak T5 trans in third-gen Camaros and can be swapped into earlier year Camaros with a bit of fabrication.

    Top Searches
    • [​IMG]4/11
      This is TCI’s Converter Lockup Control Wiring kit (PN 376600), which allows installation of an overdrive automatic trans with a lockup converter in any non-computer-controlled car.

      The JET Performance Products Transconversion kit enables the installation of an electronically controlled 4L80-E automatic overdrive trans into any carbureted or fuel-injected car. Its stand-alone computer is programmed to control all trans functions and features a diagnostic port for connection to scanning equipment.

      Swapping a TH200-4R trans into an early Camaro chassis is simple if you use an original TH400 trans crossmember like this one from Classic Industries. The TH400 and TH200-4R share equal dimensions, and only a TH350 or Powerglide slip-yoke is needed to finish the mechanical portion of this swap.

      Installing this TH200-4R into a lowered ’67 Camaro required the fabrication of a 3/8-inch-thick aluminum spacer to raise the rear of the transmission and keep driveline angles in sync. In some swaps, it may be necessary to lower the rear of the trans, especially after moving the crossmember back to accommodate a longer trans.

      This is the Centerforce clutch, flywheel, and pressure plate assembly needed to install a T56 transmission behind an early, two-piece rear-main-seal block. The hydraulic clutch master cylinder assembly for the T56 (PN 12559912) can be purchased complete and pre-bled, ready to install from any Chevrolet dealer.

      This custom bracket is made from aluminum flat stock and features the proper 22-degree angle for the T56’s hydraulic master cylinder. This bracket, along with the corresponding clutch pedal tab, which gets welded to the factory pedal, must be used to install a T56 hydraulic pull-off-style clutch. They are both available from Westcoast Connections, which can be reached at 707/546-9714.

      If you’ve bought a used T56 from the scrap yard, the cable-driven speedo in your Camaro won’t work. JTR offers modified extension housings (bottom) for the T56 that allow hookup of the cable and gears for proper speedo operation.

      While swapping in any of the automatic overdrive transmissions probably won’t cause an exhaust clearance problem, swapping a big T56 into a slammed Camaro may give you nothing but the “scrapes.” It may be necessary to have custom headers fabricated and to install a ministarter to clear the bellhousing.

      This is one of those stories that you’ll want to add to your ever-expanding files of Bow Tie knowledge. This trans swapping guide is for early Chevrolet iron and concentrates particularly on first- and second-generation Camaros. It may be the most complete resource guide the crack Chevy High Performance editorial staff has ever created. We have gone to great lengths to supply you with as much swapping information as could be dug up. This guide can tell you what’s involved with—and needed for—swapping any trans into your Bow Tie.

      Easy Swaps


      By far the most popular conversion is swapping out an original two-speed Powerglide (PG) for a three-speed TH350. The TH350 is a bolt-in replacement for a PG, making this swap a relatively straightforward one that requires no crossmember or driveshaft modifications. The TH350’s steeper First-gear ratio will give you improved acceleration over the two-speed ’Glide. The stock console shifter that controlled the PG will work with the TH350 as well, but you may want to replace the stock indicator bezel with one from a TH350- or TH400-equipped car to keep track of what gear you’re in.

      The next easy swap involves replacing either a PG or TH350 with the bigger, stronger, and heavier TH400. This swap is pretty straightforward in any early Chevy, considering that TH400s were optional in most of them. When changing from a PG/TH350 to a TH400, the stock trans crossmember will need to be moved back several inches to align with the TH400 trans mount. If your vehicle ever came equipped stock with a TH400 trans, then you could pick up a crossmember from the scrap yard or a source like Classic Industries, which would allow the TH400 to bolt right into your stock frame. The original TH350 and PG driveshaft won’t need to be shortened because it’s already the correct length, but you must replace its slip-yoke with a 32-spline unit from GM (PN 14075214).

      The TH400’s torque converter features a different diameter bolt circle than the TH350/PG converters, but most GM flexplates are already drilled with the necessary dual pattern. If your flexplate has only one bolt circle, you’ll need a dual-pattern replacement, readily available for all Chevy V-8s from sources such as ATI, TCI, and Pioneer. The fittings for the trans cooler lines are in the same location on all three of these automatics, so the plumbing won’t need to be modified. And the same shifter can be used to control either a TH350 or TH400.

      Overdrive Automatic Swaps

      Starting in the early ’80s, GM began installing four-speed automatic overdrive transmissions to improve gas mileage. Another benefit of these overdrive transmissions was that they featured a much deeper First-gear ratio, giving improved acceleration off the line. Today, the three-speed automatic transmission is extinct and all new GM cars and trucks come with overdrive four-speed automatics, making them easy to find and relatively affordable.

      4l60/TH700-R4 Swap

      By far the most common overdrive swap has been replacing a three-speed automatic trans with the popular 4L60/TH700-R4 unit. Just so there’s no confusion about which transmission we’re referring to, the 4L60 was the first upgrade made to the venerable TH700-R4. The 4L60 preceded the electronically controlled 4L60-E, which currently comes stock in most of GM’s V-8–powered cars and ½-ton pickups. The nonelectronic 4L60 and TH700-R4 are essentially the same transmissions as far as swapping is concerned, so we’re going to lump them both into the same category. This swap requires minimal fabrication skills and very little in the way of custom modifications.

      The TH700 is equipped with a removable tailshaft housing that has varied in length for different vehicles over different years. The tailshaft housing to look for if you’re replacing an original TH400 trans came stock on mid-’80s police cars (Caprice) and the early Impala SS. This tailshaft housing puts the mounting pad almost in line with the original TH400 pad and usually requires only slight elongation of the mounting holes to fit. If you’re replacing a TH350 trans, you can relocate the factory crossmember mounting holes rearward approximately 1½ inches or swap in an original TH400 crossmember.

      For either swap, the driveshaft will have to be shortened by as much as 3¾ inches. We recommend mocking up your installation with the TH700-R4 trans in place and then taking measurements to determine how long your new driveshaft will need to be before having it cut. A TH350/PG slip-yoke will work with the TH700-R4 trans, but a TH400’s will not. The TH700 uses a unique torque converter that will bolt right up to a TH350’s flexplate.

      TH200-4R Swap

      The TH200-4R has been available almost as long as the TH700-R4 but is unanimously overlooked as a performance transmission option. Truth is, the TH200-4R is just as capable and actually easier to swap in than a TH700-R4. It is ideal if you’re replacing a TH350 or Powerglide trans because a TH200-4R will practically install itself into a TH350/Powerglide–equipped car. You may run into transmission oil-pan interference problems when bolting the TH200-4R into early Camaros with the stock TH400 crossmember. The easiest cure is to fabricate a steel or aluminum spacer to raise the back of the trans and slip the spacer in between the mount and the transmission to give it the necessary clearance (see photo). Also, the TH200 uses a torque converter with the smaller TH350 bolt circle. You may have to switch to a dual-pattern flexplate if your car came equipped with the TH400 trans.

      Lockup Control

      GM had a good idea when it installed lockup torque converters in the overdrive automatics. The purpose of the lockup is to couple the engine directly to the transmission’s output shaft in Fourth gear for the best fuel economy. One design dilemma that comes with the lockup converter is that the transmission only sees full oil pressure when the converter is locked. This can lead to transmissions running hot and living a short life behind a powerful engine. But most aftermarket performance transmissions are valved to alleviate such problems, and running a supplemental trans oil cooler is always a good idea.

      ACT manufacturers a special High Pressure Valve (PN 17008) that allows the trans to see maximum oil pressure with a non-lockup-style converter, and they don’t recommend combining it with a lockup converter. TCI offers a wiring upgrade kit, which allows installation of a TH700 or TH200 with a lockup converter into any non-computer-controlled car. This wiring kit uses two sensors to control converter lockup at the proper time. The first sensor only engages the lockup clutch in Fourth gear, as a computer-controlled vehicle would. The other switch gets connected to a ported vacuum source and measures engine vacuum. This switch unlocks the converter if the engine is making less than 8 inches of manifold vacuum. So when the throttle is either wide open or completely closed, the converter clutch is unlocked, allowing converter slippage. This also acts as a safety to ensure that the converter will unlock before the vehicle comes to a stop.

      Automatic Shifting Control

      All of GM’s overdrive automatics use a cable connected to the throttle that tells the transmission when to shift. If this cable, called a Throttle Valve Cable (or TV cable for short), is connected incorrectly or misadjusted, the trans will shift too soon, too soft, too late, or not at all. Chevy High Performance outlined proper adjustment techniques for the TV cable back in the Mar. ’99 issue in a story titled “Hard Hittin’ Shiftin’” on page 66. If you’ve installed your overdrive and the trans won’t shift right, read that story and check out your adjustment. Holley, TCI, ACT, and GM all offer cable attachment brackets to facilitate TV cable connections to any carb. Also, there is no vacuum modulator used on the TH700/TH200, so you can plug the old line that ran from the base of the carb or intake manifold to the transmission.

      4L60-E And Its Big Brother The 4L80-E

      It’s ironic that even though both of these strong overdrive transmissions come stock in all of GM’s automatic-equipped new cars and trucks, not many of them are finding their way into early performance musclecars. Perhaps that’s due to their weight and high initial cost. Or maybe it’s because they’re hard to find used in the scrap yards and many people don’t want to add a computer just to control the transmission. To make that task easier, JET Performance Products now offers a stand-alone computer-controlled system that will operate a 4L80-E transmission behind any carbureted or fuel-injected engine.

      The 4L80-E Transconversion kit features its own computer with software that is custom-tuned to your vehicle’s specifications, providing the proper shift points, shift quality, and lockup torque converter function. Its wiring harness has a built-in diagnostic port that will allow the connection of the modern scanning electronics present in any Chevrolet dealership’s garage to track down and diagnose any transmission-related problems. The JET system will not interfere with any existing computer systems you may have already installed in your vehicle.

      Manual Gearbox Swapping

      This is where things get complicated—not because swapping an older four-speed or even a newer factory five-speed is all that difficult, but instead because there are so many different variations of manual transmissions floating around today that just knowing what you’ve got is a big step in the right direction. Chevy High Performancehas covered the transplant of GM’s T56 six-speed manual transmission into early Chevys in several stories (see “Get Six,” Sept. ’98, and “Get Six, Pt. II,” Feb. ’99; “Thrasher,” Oct. ’98; and “Trans Swapping Tech,” May ’99) so we highly recommend referring back to those issues for details concerning a T56 swap.

      Several companies are now offering parts to help make swapping in a T56 a whole lot easier. One part is a completely new aftermarket T56 transmission assembly from National Drivetrain. All T56 transmissions installed in late-model cars use an electronic pickup to measure speed, but National’s T56 is designed to use the standard speedo cable and T5 manual transmission’s drive and driven gears. This T56 is a direct replacement for the weakling T5 trans that came stock in third-gen Camaros. Its case length and mounting pad are identical, and it features the same input/output spline count as the T5. It does require that the clutch be converted to a hydraulic pull-off design using a hydraulic master cylinder and remote fluid reservoir. Centerforce has come to the rescue and offers a clutch, flywheel, and pressure plate made to adapt this trans to early, two-piece rear-main-seal small-blocks.

      Swapping any six-speed trans into your early Chevy iron is expensive and difficult, but it will give you the ultimate in shift control and cruising speed. There is much custom fabrication work involved in a six-speed swap as well as some additional high-performance hardware that you’ll need, including purchasing or fabricating a custom mounting bracket and modifying the stock clutch pedal for the hydraulic-clutch master cylinder, modifying or fabricating a complete transmission crossmember, relocating the shifter hole in the floor of the car, shortening the driveshaft and possibly changing its yoke, and even installing a small-diameter starter and having custom headers built for clearance. This may sound like a lot to swallow in one gulp, but one astute reader sent us a very detailed list outlining the modifications needed and the costs involved with making his T56 swap a reality. Roughly $3,000 later and after some very inventive engineering, he was rowing a T56 six-speed in his ’69 Camaro (see “Get Six, Pt. II,” Feb. ’99). We won’t say a T56 swap is a bad idea, but it’s not for the timid or frugal.

      There are other aftermarket manual trans options available for the early Chevy crowd that won’t cost more than the down payment on a new car and are much easier to complete. One such swap involves installing a Richmond four-, five-, or even six-speed manual transmission. The Richmond gearboxes are unique in that they can be ordered with a variety of gear ratios to fit different driving styles. Only the Richmond four-speed trans is a direct-fit replacement for the ’71-and-later Muncie and Super T-10 transmissions using the same 26-spline input and 32-spline output shafts. Its overall dimensions are very close to either of those gearboxes, so the Richmond four-speed can be swapped into any car in which a ’71-and-later Muncie or Super T-10 was optional.

      The Richmond five-speed is known as the Street Five-Speed and also uses a 26-spline input and 32-spline output shaft. It also has essentially the same dimensions externally as the pre-’71 Muncie and old T-10. The only modifications needed to install a Richmond five-speed in a pre-’71-Muncie– or T-10–equipped car would be moving the crossmember back approximately 2½ inches. The Richmond Street Five-Speed is not an overdrive trans and can only be ordered with a 1:1 Fifth-gear ratio.

      Richmond’s bad-boy overdrive six-speed is a whole different beast from the rest of the six-speeds on the market. Some of the benefits of the Richmond six-speed is its light weight (108 pounds) and its ability to use a regular-style mechanical clutch and linkage from an early Chevrolet. The six-speed Richmond box is also available with either a 10- or 26-spline input shaft, and is an easy swap for early 10-spline–equipped Muncie and T-10 cars because its overall case length is equal to a Muncie or T-10. The rear mount on the Richmond six-speed will require a custom-fabricated crossmember—installed approximately 6 inches farther back—or it’s often possible to relocate the existing crossmember rearward. The new Richmond six-speed trans comes with its own six-speed shifter assembly that will require elongation of the shifter hole in the floor.

      More can always be said and learned about any topic as vast as transmission swapping—a whole book could be written on this subject—but we’ll try to condense all the important information and pass it along to you as it becomes available. Feel free to write in with questions concerning your particular swap. We can’t answer your question directly, but we may address it in a future story, so stayed tuned.

      Classic Industries
      Huntington Beach, CA 92648
      TCI Automotive
      Ashland, MS 38603
      National Drivetrain
      Chicago, IL 60609
      ATI Performance Products
      Baltimore, MD 21207
      Centerforce Clutches
      Prescott, AZ 86301
      JET Performance Products
      Huntington Beach , CA
      Original Parts Group Inc. (OPGI)
      Seal Beach, CA 90740
      Rochester, NY 14625
      Advanced Adapters
      Paso Robles, CA 93446
      Year One
      Tucker, GA 30085
      Auto-Rite Transmissions
      Van Nuys, CA 91411
      Pioneer Performance Products Barnes Group Inc.
      Meridian, MS 39301
      ACT Performance Products (All Custom Transmission)
      Van Nuys, CA 91406
      Art Carr Performance Products\t
      Reno, NV 89512
      Denny’s Drive Shaft Service
      Kenmore, NY 14217
      Jaguars That Run (JTR)\t
      Livermore, CA 94551
      Westcoast Connections
      Santa Rosa, CA 95407
  2. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Its Ironic Grumpy.
    Turbo 400 weighs just 135 lbs.
    700R4 & 4l60e weighs 175 lbs.
    4L80e weighs 255 lbs.

    I had 2 4L80e's.
    They were heavy to pick up and carry.
  3. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    For me Turbo 400 can not be matched for strength.
    Low cost to build yourself.
    Vast Race torque converter selection.
    Time proven durability.
    I dont need Overdrive like most.
  4. Mark Bradley

    Mark Bradley Da guy in Newbury

    Interesting that the TKO line is not mentioned.
  5. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member


    just a bit of info, if you want a new transmission,core for spare parts,
    I called the local "U-PULL-AUTO-PARTS"
    and the salvage yard quoted me $220
    and I asked again, any auto trans regardless of make/model/year?
    and was told yes..
    but that trans does not come with a warantee its looked at as a core
    so Id be looking for a car/truck, source ,that had been in an accident as it had to be running to be driving,
    if the car/truck you pull it out of,
    is undamaged it MIGHT be in the salvage yard,
    because the trans failed.
    Id also look to see if theres indications,
    the car/truck had been under water or in a fire,
    that might have damaged the transmission

    most local salvage yards have no real clue whats out in the yards as inventory changes constantly,
    youll need to get out and look and have a detailed list of the cars/trucks that had the parts you need,
    keep in mind some yards specialize in older cars and some just take what comes in and scrap older cars on a constant basis.
    and ideally the pictures of those cars and trucks,(makes the potential donors easy to spot)
    and a pick-up truck, with, a set of portable tools and a decent floor jack and jack stands and a wheel barrow if you decide to pull the trans,
    from the local (U-PICK-IT) salvage yard , just get a written quote BEFORE you go through all the work and try too get them to specify,
    it includes the trans, converter , shiftier and drive shaft yoke, at a discount price if you buy the transmission, and need that list of extra parts



    maker weight gears type source comment

    Alfa Romeo 195 manual (166) '76 Alfetta GT transaxle

    Borg Warner 101 4 speed manual Ford Super T-10 iron/aluminum

    Borg Warner 92 4 speed manual Chevy Super T-10 iron/aluminum

    Borg Warner 130 4 speed manual (158) 1927 model T-4, for 1927 Paige 8 (dry)
    rated to 175 ft-lb

    Borg Warner 78 5 speed manual (85) T-5, Ford pattern

    Ford 48 4 speed manual (85) '71 Capri/Pinto 1600 light duty
    (iron case, aluminum tailshaft housing) iron bhsg 23#

    Ford C6 ~202 3 speed auto (152) Big block C-6, 165 lbs, Transmission
    weight, drained, without torque converter 37 lb, Torque converter
    weight, mostly drained

    Ford C6 ~171 3 speed auto (154) no fluid

    Ford C4 ~185 3 speed auto (152) Small block C-6, 150 lbs, Transmission
    weight, drained, without torque converter 35 lb, Torque converter weight, mostly drained

    Ford AOD 184 4 speed auto (154) (without fluid)

    Ford AOD 195 4 speed auto (159) including torque convertor

    Ford FMX ~195 3 speed auto (154) cast iron case

    Ford FMX 195 3 speed auto (159) iron case

    Ford 228 3 speed auto (154) Ford-O-Matic (pre-FMX), cast iron case (early '60s)

    Jerico 72 4 speed manual (145) mag. case with integral coolant pump

    Jerico 68 4 speed manual (145) mag. case w/o integral coolant pump

    Jerico 52 2 speed manual (149)

    Land Rover LT77 5 speed manual 95

    Land Rover R380 5 speed manual 118

    Mitsubishi 110 5 speed manual (146) '91 VR4 transaxle, less transfer

    Porsche 89 5 speed manual (147) 901 transaxle

    Porsche 109 5 speed manual (147) 915 transaxle

    Saginaw 149 4 speed manual (147) Corvair IRS transaxle

    Saginaw 82 4 speed manual (85)

    VW 71 4 speed manual (147) Beetle IRS transaxle

    VW 79 4 speed manual (147) Bus IRS transaxle

    ZF 135 5 speed manual (147) Pantera transaxle

    GM Transmission Information (Looking for Engine info? Click here)

    This page has been set up to bring you the most accurate and up to date information on GM transmissions that is available to us. This information should be used as a guide only. While we have made every effort in making the information presented here as factual as possible, but there still could be some discrepancies or errors. If you have any questions, comments, or suggestions, please give us an email.

    Front-Wheel Drive Transmissions

    4T40-E / 4T45-E

    • FWD 4-speed automatic with overdrive
    • 187 lbs transaxle weight filled
    • Gear Ratios:
    • 1st -- 2.960
    • 2nd -- 1.626
    • 3rd -- 1.000
    • 4th -- 0.681
    • Rev -- 2.143
    • Final Drive Ratios: 3.05, 3.29
    • Available Chain Ratios: 35/35, 33/37, 32/38

    4T60-E -- click here for Application ID charts

    • FWD 4-speed automatic with overdrive
    • 204 lbs transaxle weight filled
    • Gear Ratios:
    • 1st -- 2.921
    • 2nd -- 1.568
    • 3rd -- 1.000
    • 4th -- 0.705
    • Rev -- 2.385
    • Final Drive Ratios: 2.84, 3.06, 3.33
    • Available Chain Ratios: 35/35, 37/33, 28/27, 33/37

    4T65-E -- click here for Application ID charts

    • FWD 4-speed automatic with overdrive
    • 214 lbs transaxle weight filled
    • Gear Ratios:
    • 1st -- 2.921
    • 2nd -- 1.568
    • 3rd -- 1.000
    • 4th -- 0.705
    • Rev -- 2.385
    • Final Drive Ratios: 2.84, 3.06, 3.33
    • Available Chain Ratios: 35/35, 37/33, 33/37


    • FWD 4-speed automatic with overdrive
    • 293 lbs transaxle weight filled
    • Gear Ratios:
    • 1st -- 2.960
    • 2nd -- 1.626
    • 3rd -- 1.000
    • 4th -- 0.681
    • Rev -- 2.130
    • Final Drive Ratios: 2.84, 3.11, 3.48, 3.71

    FWD Transmission Gearing / Chain Information Table

    Rear-Wheel Drive Transmissions


    • RWD 4-speed automatic with overdrive
    • 159-176 lbs transmission weight filled
    • Gear Ratios:
    • 1st -- 3.059
    • 2nd -- 1.625
    • 3rd -- 1.000
    • 4th -- 0.696
    • Rev -- 2.294
    • Max Gearbox Torque: 670 ft-lbs


    • RWD 4-speed automatic with overdrive
    • 260 lbs transmission weight filled
    • Gear Ratios:
    • 1st -- 2.482
    • 2nd -- 1.482
    • 3rd -- 1.000
    • 4th -- 0.750
    • Rev -- 2.077
    • Max Gearbox Torque: 885 ft-lbs


    • RWD 5-speed automatic with overdrive
    • 186 lbs transmission weight filled
    • Gear Ratios:
    • 1st -- 3.42
    • 2nd -- 2.21
    • 3rd -- 1.60
    • 4th -- 1.00
    • 5th -- 0.75
    • Rev -- 3.02
    • Max Gearbox Torque: 494 ft-lbs

    GM RWD Torque Converters

    Starting 1980-up, GM used a 4-digit ID sticker located on the converter body to help identify it. Below is a guide to help decipher it's meaning.

    1st Digit (application trans)

    • B -- THM250C, THM350C
    • C -- 200C, 2004R, Pre-1984 1/2: 325-4L & 700r4
    • D -- 1984 1/2-up 700r4, 4L60, 4L60-E
    2nd Digit (approx stall, depends on engine)

    • B -- 2025 rpm
    • C -- 2075 rpm
    • E -- 1654 rpm
    • F -- 1611 rpm
    • G -- 1397 rpm
    • H -- 1397 rpm
    • K -- 1211 rpm
    • L -- 1654 rpm
    3rd Digit (Clutch Assembly)

    • 3 -- Poppet Valve
    • 7 -- Poppet Valve
    • 9 -- Poppet Valve
    • A -- Red (pre-96)
    • A -- Carbon (96-up)
    • B -- Static Open
    • G -- Carbon Fiber
    • H -- Red (pre-96)
    • H -- Carbon (96-97)
    • H -- Woven Graphite (98-up)
    • L -- Carbon Fiber
    • N -- Woven Graphite
    • P -- Woven Graphite
    4th Digit (Body Mounting)

    • C -- 3 round lugs, gas engine
    • D -- 3 round lugs, diesel engine
    • E -- 6 round lugs, gas or diesel
    • F -- 3 square pads, gas or diesel
    • G -- 3 square pads, gas or diesel
    If there is no ID tag, there might be a number or letter stamped between the dimples of the impeller on the converter body.

    • 4 -- 1211 stall
    • 5 -- Medium or high stall (depends on stator)
    • 6 -- 1397 stall
    • 7 -- 1654 stall
    • C -- 2075 stall
    • H -- 1397 stall
    • K -- 1211 stall
    • L -- 1654 stall

    GM FWD Torque Converters

    GM uses the same type 4-digit ID method of identifying FWD torque converters as with the RWD units, however the digits have different meanings. All 125-C, 440-T4, 4T60, and 4T60-E transmissions use the same style torque converter, and they are interchangeable before 1996. 1996-up converters are built to be compatible with GM's PWM TCC apply strategy which means that you can use the newer converter on the older trans, but not the older converter on the newer trans.

    1st Digit (application trans)

    • F -- 125C, 440-T4, 4T60, 4T60-E (245mm)
    • J -- 4T65-E HD (258mm)

    2nd Digit (approx stall (depends on engine)

    • A -- 2795 rpm
    • B -- 2560 rpm
    • C -- 2385 rpm
    • D -- 2095 rpm
    • E -- 1865 rpm
    • G -- 1630 rpm
    • H -- 1515 rpm
    • J -- 2060 rpm
    • K -- 2760 rpm
    • L -- 1895 rpm
    • M -- 1525 rpm
    • Y -- 1420 rpm
    • Z -- 2375 rpm

    3rd Digit (TCC clutch material)

    • 0 -- Clutch omitted by factory
    • 5 -- Clutch contains poppet valves
    All other digits(pre 1996):

    • Red Fiber material

    • C, E, H, K, P -- Carbon filled clutch

    • F, H, K, Q -- Woven graphite clutch

    4th Digit (Clutch Type)

    • B -- standard
    • C -- viscous

    Pertaining to the TCC Clutch material: starting in 1996, GM implemented a new TCC apply strategy. The 1996-97 trannys (exc 3T40), used a soft-apply (PWM) TCC strategy which was designed to soften the TCC apply so the "customer" would not feel it come on. This means that the PCM is actually making the TCC slip during apply. Only Carbon clutch torque converters should be used in 1996-97 trannys. You can use the carbon clutch TC's in earlier trannys that did not have PWM technology, however the lockup feel will not be the same. However, I have heard that these carbon clutches rarely burn-up or go bad. I have personally used the carbon filled clutch TC's on earlier trannys and the only experience I have witnessed with them is they apply firmer.

    Starting in 1998, GM revised the lock-up strategy once again only this time the TCC may never completely lock up and may always slip about 20-60 rpm, depending on the vehicle. This means that even the carbon clutch units would not work well for these applications thus GM started using woven-graphite TC clutch material. I have heard that the woven graphite TC's should not be used in any earlier transmissions because the lockup will not work correctly.

    This information should be used as a reference guide only. Please consult your local dealership or transmission shop for your specific application and needs.


    For the most up-to-date information on GM Powertrain, check out the GM Media Center at:

    Last edited: Aug 20, 2018
  6. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    The Torque Rating on the 4L60e is a Blantent flat out lie.
  7. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member


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