Transmission oil cooler for 2007 Chevy 2500HD 6.6L diesel

Heard good things about the "Mike L Cooler". Believe he's out of Inglewood, CA but ships anywhere.

It looks like the PPE is the same as the Mike L cooler. It was designed by Mike L, but PPE put their name on it.

You might also want to change out the transmission oil pan at the same time to one with larger capacity and better cooling.

Mag-Hytec pans

Bill

i added a pan.

I was seeing temps over 240 during climbs.
What I have experienced is cleaning the cooling stack (where the components are removed from the truck and then cleaned) can really bring temps down. Its extremely hard to clean between radiator and intercooler while still in truck. Rarely see 200 now.
I don't know if you have a the classic or new body style. I know with my 2010 the radiator came out from the rear after fan was removed. So it was unnecessary to remove AC coil and intercooler. Just washed those out from behind after radiator was removed.
The problem with the Duramax is the transmission is first cooled through the radiator and then goes to an air cooler. If the radiator isn't cooling the engine coolant effectively it will make the trans fluid even hotter.
So a plugged up radiator will cause your problem.

I have never heard of anyone needing an aux cooler on the GM Allison factory set up. What temps are you seeing?

I've seen temps in the 205-210 range, but I haven't pulled my new toy hauler in the high summer heat yet. I bought it last September, and it was in the low 90's when I drove it home. Since then I've only towed when it was in the 70's at the highest.

We're going to the beach a few times this summer and we might make a trip to West Texas. I figure an aux cooler will help keep the temps down, which definitely won't hurt anything. Plus, my truck is almost 8 yrs old, so anything I can do to help the old girl out will be helpful.