I'm stock except for the exhaust. I don't tow very much... but when I do, we put 600 miles on in a day. I don't know how heavy the 28' Tahoe TranSport is but I found one year listed as 7000 dry weight / GVW of near 10,000 (a second listed GVW of 12,000). Truck (see signature) has Tow Package which includes a transmission cooler. I haven't been able to add guages yet. Note: I've discovered 4.10 is the wrong gear ratio with stock tire sizes but I own the truck now. As I posted previously, I pretty much have to use OD on flat & downhill, kick the OD out & drop speed if the truck is unhappy on a grade (no issues except loss of cruising speed). I'd like to bump the power just a bit to improve the ability to hold speed on the hills. I'm assuming it is better to plan a transmission upgrade BEFORE the transmission goes South!Russ