Mostly just keeps your revs up. It waits longer to shift up and keeps you mostly out of overdrive. Also gears you down quicker when decelerating to let the transmission help the brakes amd be able to pick back up when you get back on the throttle.

I find the tow/haul is more aggressive when it comes to downshifting. I like the mode when towing or have something heavy in the bed. My 2002 Duramax was much more aggressive in shifting with the Allison transmission. Towing the 5th wheel was a breeze.

quote:

Originally posted by Mars_Attacks:
Tow/Haul transmissions get a different set of clutches, thrust bearings and steel planet carriers.

In what brand and type of vehicle?

quote:

Originally posted by Black92LX:
Completely different truck they should call it beast mode.

Over at Tundras.com, that's exactly what they call it.