After towing my 5,500 Travel trailer up and down some of Northern Florida's rolling hills ( I currently have 2017 4.8 V8) engine wan working a bit hard going up hills, couldn't accelerate, up hills would downshift to 4h gear and occasionally 3rd gear, I'm considering upgrading to the 2021 with 6.6 liter gas engine, but I hear they removed the external transmission cooler? should this be a serious concern? Any GM experts out there with your thoughts?

 

If you think it is a concern $100 would get you an aftermarket trans cooler.

 

modern trans with so many gears they can lock the convertor up much earlier...this translates to less fluid shear and lower fluid temps. Would it bother me to run stock, nope...as long as i'm within the tow limits and realize i need to follow the severe service interval for fluid change.

Would a cooler be better...sure....lower fluid temp equates to longer fluid life.

What i find comical is people overloading a vehicle and adding secondary coolers thinking that is the fix.