When I got the new truck I was so happy with just using the button on the shift lever to downshift in the mountains because it was so much better than the old 4 speed trans and working the shift lever and OD button. Then I discovered tow/haul and use it all the time with the TC and even us it some empty when heading downhill. Just touch the brake a bit and it takes it down a gear each time and holds it until the go pedal is pushed. Now I hardly use the up/down buttons since I find tow/haul a better option. I also like the way it shifts better in tow/haul as an added bonus. Now if there was just a way to have it come on as soon as the trailer connector is plugged in.