Excess heat is the bitter rival of any vehicle, but especially when it comes to heavy-duty trucks, like the 2015+ 6.6L Duramax powered Chevys and GMCs. The HD Silverado and Sierra are already mega heat-generating machines on their own. Still, GM designed these trucks for the express purpose of pulling, towing, hauling heavy payloads, and generating even more heat. While you might have opted for the Heavy-Duty Duramax powerplant, the engine is only half of the equation. No matter if you chose to upgrade to the coveted Allison gearbox or not, the transmission is the other half of what slots these trucks into the Heavy-Duty category. Keeping those gears at prime operating temperature is vital and exactly what we have in mind.
GM also had the same thought and has been including an external transmission cooler on all their trucks since at least 2001. Like the coolers found installed