Trans Cooler Install On Lincoln Navigator

I got my new OEM cooler line in so I was ready to start making changes. But just to make sure things
would go as expected, I spliced into the cooler circuit with some 1/2 inch polished SS tubing. I started
the engine and watched for 4-5 minutes and nothing went wrong, but then I turned my back and went
to the front bench in the garage. That's when I started smelling something hot, when I turned around
the line had pushed it's self of the tubing I used for the splice. By the time I shut the engine off it had
pushed out just over 2 quarts of fluid. I did have a pan under the Nav that caught most of the fluid, but
about 1 cup was on the ground.

FP17_RadiatorBypassTest_01453.jpg

FP17_RadiatorBypassTest_01457.jpg

So I replaced the SS tubing with some aluminum tubing which I roughed up with some emery cloth
before installing. This seemed to hold for 20 minutes with no problems. I then went for a 30 mile
highway cruise and it was working with no unexpected consequences.

While watching the setup before leaving on the 30 mile cruise, I measured both input/output lines to
the OEM cooler. There was a consistent 15°F difference across the cooler with the hottest line going
across the the bottom of the cooler in the photo below. I did have a floor fan blowing across the cooler
to help make a greater difference between the input and output lines.

FP17_RadiatorBypassFinalConfig_01461.jpg

To make sure I didn't have the same problem as above with the line coming off, I slightly flared the
end of the steel line I cut thru. It was still easy to push the new hose from NAPA that I bought.

FP17_RadiatorBypassFinalConfig_01459.jpg

FP17_RadiatorBypassFinalConfig_01454.jpg

So I can now confirm that I have configured the system with the OEM cooler first, then it
goes to my remote filter and Derale remote cooler, like shown below. [Filter not shown]


FP17_CoolerDiagram.jpg

It's the same photo as above, but this is my final configuration. So far all I can tell is the fluid temp heats
up slower, but with the weather cooling off, it's going to be nearly impossible to do a good comparison. Guess
it will be next year, so much for a scientific study.

FP17_RadiatorBypassFinalConfig_01461.jpg
.
 
When ever I do lines with rubber hose being pushed onto it, I use my brake tubing flaring tool to put a bulge at the end of the tubing so the clamp will hold the hose on better. Dog knot if you no what I mean.
 
Changed the Wix remote filter for the trans after 8,485 miles to see if it was catching
anything. It seemed to be perfectly clean.

FP01_WixRemoteFilter_02387.jpg
FP01_WixRemoteFilter_02390.jpg
FP01_WixRemoteFilter_02391.jpg
 
OK, I think I might have screwed the pooch as the situation below started to unfold.

Working on adding another trans cooler to my Lincoln Navigator in the front of the radiator. It's nearly
impossible to push the braided hose onto a barb fitting, so when I saw they could be removed I did so.
When it looked like I might be able to screw a ORB AN fitting in place of the OEM fitting, I tried to screw
the ORB-AN fitting into the cooler fitting in the radiator. But what actually happened is, the coils in the
radiator pushed back and fell into the radiator ........

Now all of sudden I have coolant going everywhere, rushed around and got 2 pans to put under the
Navigator to catch what I could. Now that the immediate emergency is over and I've had some time to
analyze the situation, I was able to get the OEM fittings started again and also verify I had the internal
gasket is in place. I have an o-ring kit, so I was able to install a new o-ring for the external seal.

From now on I will only remove ONE fitting at a time. That was a close one !!!

The threads look to be the same on both fittings, but the AN fitting will not start. I measured the threads
on the OEM fitting and both 16 tpi and 1.5 threads per mm are so close I can't tell which one is right.

Long shot, does anyone know what thread I'm really dealing with in the radiator ??? If it's metric,
then a 18mm-1.5 would be a possibility. I sure would like to use an AN fitting in the radiator, it would
simplify installing the new Derale 40 row stacked plate cooler for the trans.

The photo below is to give you a big picture look at my problem

FP01_FluidLineRouting_02828.jpg


There is an internal gasket for the trans cooler, that should be so easy to work with since I cannot touch it !!! :(


FP02_UpperTransCoolerLine_02859.jpg
FP02_UpperTransCoolerLine_02861.jpg


I have not been able to screw the -8AN fitting into the radiator trans cooler. So I have to wonder if the threads might be metric ???

FP02_AN_vs_OEMFitting_02862.jpg

Damn, what a mess I've gotten myself into with my daily driver !!! LOL !
.
 
Last edited:
Rick I don't have an answer to your question... but I would think that your vehicle being a 2008 model would
definitely be metric.
 
The other concern is the O-Ring seal, will
just have to try it out and see if it works.

Not sure what you meant by that...
Yes , there is an o-ring used on the metric side..but not on the AN side as it seals against the taper seat. I'm sure you already knew that.
 
The metric adapter is not designed to use an O-Ring, so that is my concern. Will it work anyway ?
 
The metric AN adapter worked, the radiator thread is a M18 x 1.5. I tried it without an O-Ring and
it sealed with only the internal gasket, so I don't know why they put one on the fitting. But I still put
an o-ring on the new AN fitting. In the photo it looks like it is pushed out, so it's not really doing
anything. The problem is because the new fittings were a 7/8 inch wrench while the old OEM fitting
is 1 inch.

https://www.summitracing.com/parts/rus-670560

FP04_MeticAN_InstalledInRadiator_02919.jpg

Wonder what others would do with the 7 row OEM cooler shown in the photo below, keep it, or
delete it ???

If I delete the OEM cooler, then I can use AN fitting everywhere. If I keep the OEM cooler, then it
have 2 barb fittings.

FP01_FluidLineRouting_02828.jpg
 
Well... Are you after looks or extra cooling? Personally , I would keep the cooler. The factory must think the barbed fittings were OK.
 
I would keep the cooler. The factory must think the barbed fittings were OK.
Yeah, I've not had any problems with the barb fittings leaking. The OD of the barb is too big to just
slide the braided hose onto the barb. I will have to reduce the OD to get the new hose on the barb.

It's a simple matter to remove the OEM cooler.
 
Last edited:
I came up with a better solution for the OEM cooler. I converted it to AN with a Compression Fitting
to AN adapter.
I had to cut the tip of the barb off, since it was bigger than the rest of the fitting. After
that the ferrule slid on without a problem.

I had a AN cap so I put it on one end a poured a 1/2 cup of Alcohol in the other end. Then I pressurized
the cooler for 2 minutes with 50 psi air to check for leaks. I tested both ends with this procedure.

Now every connection in the front is a AN fitting.

FP05_ConvertOEM_CoolerToAN_02920.jpg
 
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