42RLE transmission temp problem

[MikeE024]

If you are asking about the cooler mounted in front of the radiator, no, there is not an integrated fan as with the Derale setup. The reason to mount it in front of the radiator is to take advantage of the engine fan.

This is my current setup. The tranny cooler is on the bottom. The cooler on the top is for the hydro-assist steering and brakes.

View attachment 704038

View attachment 704039

Same setup on mine. Derale for PSC hydro assist steering on top and Setrab for the 42rle on the bottom.
View attachment 704043

Jerry's continued insistence on the fan cooled Derale trans cooler was long outdated quite a while ago.

Blaine built the same setup for me. He now offers a mounting kit so folks don't have to send him their v-bar for welding.

This is the kit for folks who don't need his steering cooler or who already have one.

https://blackmagicbrakes.com/ols/pr...o-mount-the-setrab-53-10748-01-to-the-v-mount

 

[richardh]

Are you plumbing the tranny cooler inline with the factory radiator tranny cooler? Or, leaving the radiator based tranny cooler out of the plumbing?

If you are asking about the cooler mounted in front of the radiator, no, there is not an integrated fan as with the Derale setup. The reason to mount it in front of the radiator is to take advantage of the engine fan.

This is my current setup. The tranny cooler is on the bottom. The cooler on the top is for the hydro-assist steering and brakes.

 

[NashvilleTJ]

Are you plumbing the tranny cooler inline with the factory radiator tranny cooler? Or, leaving the radiator based tranny cooler out of the plumbing?

It is plumbed in line with the radiator cooler. The reason to do so is less about cooling the tranny, and more about warming up the tranny quicker when ambient temps are colder.

 

[richardh]

It is plumbed in line with the radiator cooler. The reason to do so is less about cooling the tranny, and more about warming up the tranny quicker when ambient temps are colder.

That makes sense, thanks.

 

[MikeE024]

Are you plumbing the tranny cooler inline with the factory radiator tranny cooler? Or, leaving the radiator based tranny cooler out of the plumbing?

It is plumbed in line with the radiator cooler. The reason to do so is less about cooling the tranny, and more about warming up the tranny quicker when ambient temps are colder.

I tested it without the radiator for fun last year.

As Nashville mentioned, the transmission warms up much quicker when plumbed in. Also, many folks incorrectly think the radiator will cause the transmission fluid to run hot...but the air-cooled fluid in the radiator actually helps keep your transmission temps from going nuclear.

 

[richardh]

I have now completed the following:

A complete inspection of how the tranny cooling system was plumbed. It was not plumbed according to Derale installation instructions. So, I plumbed it correctly trans -> radiator -> cooler -> trans including making all new hoses and using -6an fittings for every connection.

I checked codes found TCM had thrown over temp codes during my last trip. So, I changed out my transmission fluid. I also disconnected the return line from the trans and flushed a gallon of fluid through the system a quart at a time.

This weekend I took it wheeling up in Big Bear on Dishpan and Holcomb Creek, 2 weeks after the last time I did this trip and threw TCM codes. I saw these temps on my dash gauge hooked to a sensor in the pan.

• Cruising on the freeway about max 180 degrees with fan on, max 190 degrees with fan off
• Climbing from the Valley to Lake Arrowhead max 210 degrees with fan on
• On the trail range 160 to 170 degrees with fan on
• Cruising home on freeway around 8pm, max 160 with fan on, max 175 degrees with fan off
• I also did some testing using my diagnostic reader, the TCM generally shows temps between 20 to 25 degrees hotter than the sensor in the pan.

My conclusion is that I now have a workable trans temp situation in my 42rle.