Tow/haul mode on Chevy 1/2 ton
I'm looking for a simple, plain language explanation of what the tow/haul mode on a Chevy does. I'm assuming it changes the tranny shift points or something similar. Also, should I use this all the time when pulling our TT or is mainly a benefit for hard pulls ( mountains, high speed highways ), and does it have any braking benefits like the Allison tranny in a Chevy.
PS. I know I could search web and probably find a lot of info on this but I'm being lazy and thought some of you might be able to help and give info from your experiences. Thx