Trans Cooler Install On Lincoln Navigator


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


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

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

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 .......


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.



The Grumpy Grease Monkey mechanical engineer.
Staff member
Id slip some rubber hose or about 4" of smurf tube

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


Staff member
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.



Staff member
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.


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.


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.
Vibrant Performance 24008



Below is how it worked into my situation.


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 ???


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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