Upgraded trans cooler from Fordparts

203 is pretty good. You have to remember the fluid circulates through the radiator first. This is done to get the fluid up to operating temp quicker, heat exchange occurs between the engine coolant in the radiator and the trans fluid. The bad part is as the radiator starts to heat soak under load it puts more heat into the trans fluid which is then extracted via the secondary trans cooler. Towing puts a lot of heat in the truck, its going somewhere, if the airflow can't take it all out it's going somewhere else.

Also, the OEM temp sensor is in the valve body, this location isn't a good indicator of return temps. If you want to know how much change your actually getting you would want a sensor mounted in the pan, or in the return path.

Anthony k said:

it lowers the temp ZERO!
I drive to my cabin 3 hours away in all weather, towing a trailer every single time. I log temps and fuel.
This cooler didn’t change the temp AT ALL! not one single degree!

I make this trip 2-3x a month.
Exact same route

Click to expand...

Towing an enclosed car trailer on a 110 degree summer day (desert life), it dropped my trans temps from 228 to 205. Interesting it didn’t make a difference for you.

This mod just begs to be done, it fits the Raptor better than the original. Like others have stated the temps I'm seeing with this upgrade range from 195 - 203 during a 8-10 hour drive at 75 mph. If you are seeing trans temps in the 220+ range it's a must have.

MrGable27 said:

Towing an enclosed car trailer on a 110 degree summer day (desert life), it dropped my trans temps from 228 to 205. Interesting it didn’t make a difference for you.

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If you're Supercharged as they are it won't make much of a difference, we have a large heat exchanger in front of everything and blowing hot air at the radiator.
The only way to compensate is to have the OEM radiator fans turn on sooner and at a higher percentage.

Anthony k said:

it lowers the temp ZERO!
I drive to my cabin 3 hours away in all weather, towing a trailer every single time. I log temps and fuel.
This cooler didn’t change the temp AT ALL! not one single degree!

I make this trip 2-3x a month.
Exact same route

Click to expand...

You have to change the thermostat lol

HAP said:

I got the same results; seem to make no difference at all. But I do feel better about adding it. Just towed my boat to FL and back as I have done many times. Highest temp was 203 going over a bridge at 77mph. Normal is 195 with or without towing anything, winter or summer.

R,
HAP

Click to expand...

Need the thermostat, then it will lower temps.

B E N said:

Also, the OEM temp sensor is in the valve body, this location isn't a good indicator of return temps. If you want to know how much change your actually getting you would want a sensor mounted in the pan, or in the return path.

Click to expand...

This^^^

If you want cooler temps, You need to bypass the thermostat in the valve body with this.

I installed the bypass valve and the larger cooler. I rarely see over 200 degrees on trans temp. If you're pulling a trailer on a hot day, heat soaking from the radiator will make the temps creep up. When I get time, I'm going to try bypassing the radiator completely, just to see how much it changes the temps.