Trans Cooler Install On Lincoln Navigator

Guess I should go ahead and finish up this thread. The system is starting to take shape …….

FP06_ThermostatMountedInNavigator_02857.jpg

The cooler is a Derale 40 row Stacked Plate Cooler with -8 ORB fittings, fittings are included
with cooler.

https://www.summitracing.com/parts/der-54008
upload_2021-10-8_16-39-44.png

The thermostat is also Derale #25719 with ½ inch NPT threads.

https://www.summitracing.com/parts/der-25719
upload_2021-10-8_16-41-16.png

Lincoln in their great wisdom spec'd the trans cooler lines coming from all the way back at
the trans to the front would have Rubber connections at the front. Great, so when the rubber
goes to shit, you have to try and snake that new line in around corners and between the engine
and cross-member. Probably going to need to raise the engine to get enough room. So one of
my goals for this project was to eliminate that problem. I did just that with some SS tubing.

Going from this .......

FP07_TransHosesUnderNav_02959.jpg

To something much better ........

I'm using a compression fitting to AN adapter on the OEM steel lines after I cut the old rubber lines off. The
lines that are replacing the rubber lines are now 1/2" polished SS tubing.

FP07_TransHosesUnderNav_02980.jpg
.
 
Id slip some rubber hose or about 4" of smurf tube
12007.jpg

over the stainless lines ,
where they cross the body panels in the picture above to limit the potential for wear/damage as the lines vibrate against the body panel edges
 
Really, I would have never thought there would be a problem with wear there. But you can't go
wrong by adding more protection. I most likely will add some heater hose and I split and slide
over the tubing since I already have plenty of that around.

I was going to post this later, but it does seem to fit the subject at hand. I added these 3D printed
supports to stabilize the lines and keep them from moving around too much.

FP09_SS_Line_Supports_02999.jpg
.
 
SS tubing is notorious for being hard to seal, so I took some extra steps to ensure a leak
free connection !

The chamfering tool is 60° and the flare for AN fittings is 37°, meaning the chamfer is touching
in the bottom of the flare. So I had to rotate the drill around at an angle to polish the entire
surface of the flare.

Then I polished the inside of the flare on my buffer to get a really smooth surface like you
see below in step 3.

FP07_FlaringSSTubing_02967_02970_02972.jpg

Most AN hoses end with a female connection, but so does the tubing. So how can
you connect a hose to tubing ??? You can use a Coupler, and if you are going from
one size to another, then a coupler is what you will need. But it also adds another
SEALING SURFACE for a possible leak.

https://www.summitracing.com/parts/rus-660361
https://www.summitracing.com/parts/rus-661771

upload_2021-10-11_10-40-33.pngupload_2021-10-11_10-41-32.png

My line size was NOT changing so I was happy to see I could use a Hose-to-Male connection
made by Vibrant Performance like the one below.

https://www.summitracing.com/parts/vpe-24008
Vibrant Performance 24008

upload_2021-10-11_10-42-34.png

FP07_SS_to_HoseConnection_02974.jpg

Below is how it worked into my situation.

FP07_SS_to_HoseConnection_02982.jpg

Once I got the system plumbed, I wanted to flush the lines from all the particles created
when I cut the hose with a hack-saw. The hose has a SS layer, plus all the rubber bits that
end up in the hoses. None of it is any good for the transmission.

I had an Aeromotive 100 micron filter that I had not used, so I plumbed that into my
flushing system. Otherwise all I would be doing is circulating the trash. Wish I had a
better filter, but it's what I had.

I found a few bits of what you see below. Maybe it's was not worth the trouble, what do
you think ???

FP07_FilterAfterFlush_02983.jpg

Below is my setup for flushing the new components of my trans cooling system. I did the
same thing for my fuel system, but bypassing the carburetor.

,
 
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To help with the mounting of the Derale thermostat I designed this mount in FreeCAD
then used my 3D printer to make the bracket out of PLA plastic. PLA does not like temps
above 120°F, therefore it did warp some. But that's not a big problem, it just relieved
some stress that some of flexible lines were putting on it.

FP08_ThermostatBracketWarped_02997.jpg

FP06_FreeCadThermostatMount_01.jpg
FP06_FreeCadThermostatMount_02.jpg

I found it hard to find good places to provide support for the new lines, so I had to start
underthe vehicle with a couple of supports that are shown above in post #123. From then
on I used line clips, just like a Stud Girdlemakes all the rocker studs more rigid. I used line
clips to make all the lines more rigid.

FP09_FinishedCoolingSystem_03005.jpg


Next are my thoughts about how much the installation of two coolers have helped.
.
 
installing the filter to keep trash from circulating, or reaching the transmission internals, is almost 100% mandatory
 
I guess you are just now seeing that post. That happened just minutes before the
website went down for several days.
 
web site going down was a surprise , the website host and upgrades cost me, time & effort and a whole lot of personal time,
in getting my son to program,
time effort and fees, that cost me hundreds of dollars to rectify, and I'm reasonably sure thats not over yet, (fees/programing)
 
After installing two coolers, the 2nd cooler is a Derale 40 row stack plate cooler. Which I believe
is Derale's largest cooler of that type. I was fully expecting to keep temp from exceeding 175°F.
The reality is the temperature in the pan is still reaching 195°F when the ambient temperature is
95°F and above and I'm towing at 70 mph. With an enclosed trailer, wind resistance is a major
factor. I could slow down to 60 mph and that should drop the temperatures, but I'm not really
willing to do that.

I keep thinking that I must have gotten the wrong line coming from the trans, but I've checked
this 3 times and I keep coming up with the return line going back to the trans.

I suppose about the only thing I can do at this point is change out the fluid in the pan (about 4
quarts) every 10k to 15k miles. Not something I'm looking forward to since this trans does not
have a dipstick.

Comments ?
 
what does the current existing trans fluid temp returning to the trans look like,
before it reaches the trans?


42545.jpg


http://www.testequipmentdepot.com/e...1100200223789&utm_content=All Extech Products



and are you set up with the trans fluid routed like this ?

ARE BOTH THE FANS FUNCTIONAL AND RUNNING?


coolerdiagram.jpg
 
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what does the current existing trans fluid temp returning to the trans look like,
before it reaches the trans?
This would really need to be done with a fully loaded trailer assume. It will be awhile
before I can do that.

and are you set up with the trans fluid routed like this ?

ARE BOTH THE FANS FUNCTIONAL AND RUNNING?
Only the one cooler in the rear has a fan and the thermostat never brings it on, but I
can use the manual switch. When I do turn the fan on, it doesn't make any difference
since I'm already doing 70 mph, so it must be getting plenty of air.
 
are you sure the fans run when you hit the switch?
in theory the trans fluid will loose a good deal of heat going though the aux cooler and its also in theory already been reduced to engine coolant temp ranges before it enters the aux trans fluid cooler because it previously ran thought the lower radiator, Ive put in several, and most cars/trucks with the aux cooler have little trouble getting down to 175f
 
Are you not still within specs for trans temps? When not towing
are the temps lower?
 
Are you not still within specs for trans temps? When not towing
are the temps lower?
Temps are not a problem unless towing with a load at 70 mph and ambient temps above 90°F.
Yes temps are much lower when not towing.
 
then Id suggest the addition of a second aux cooler, in series with the current cooler might be an option.
 
Or do away with the radiator cooler which heats the fluid to t-stat temps first.
 
Or do away with the radiator cooler which heats the fluid to t-stat temps first.

thats generally a NON-ISSUE simply because the trans fluid temp exiting the transmission is RARELY entering the lower radiator at temps lower than the coolant once the engine coolant and trans fluid temps stabilize (GENERALLY IN UNDER 10-12 MINUTES OF OPERATION.)

THE TRANS FLUID IS NORMALLY HOTTER THAN ENGINE COOLANT ,
THATS WHY THE TRANS FLUID IS RUN THROUGH THE LOWER RADIATOR,
AS IT GENERALLY REDUCES THE FLUID TEMP.



now I admit I never tow with my corvette, but a decent trans fluid cooler makes a very noticeable improvement, in reducing temps




 
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