So I installed the tru-cool 40k this weekend and after a few days of driving and checking fluid levels I have averaged about a 25-30 degree drop in trans temps in everyday driving. The install is easy enough and if your nervous about it, dont be. As soon as I strap up to the 6000lb rv I will post trans temps for towing.
All of this on an 08 silverado 5.3 with 3.42 gears and 4l60e

 

What were before and after? On a hot *** day, mine before would see as high as 210, now it struggles to break 150.

 

Man you guys make me want to put one on my stock truck.

 

Do et.

Even on a stock truck, a high trans temp will severely shorten the life of it.