Ricktwuhk

U-Haul trailers have surge brakes on the larger sizes.

Velosprout

Yep; few hills here in Central Illinois and Indiana. But as an example I have a 11 1/2 foot pond bass boat with a 6hp outboard on a Shorelander trailer. Our little Jeep Patriot can tow it; we certainly don't need tow/haul mode on an F150 for such a light load even with any Southern Illinois hills.

Sweetlou

I think the better question is... why NOT use tow haul mode? In tow haul mode you have less torque converter slip, more engine braking, less lugging of motor. It's really a win, win, win. Not to mention a simple push of a button. Zero harm and plenty of benefit.

old_programmer

I don't use tow/haul unless I am in very hilly or mountainous areas when pulling our travel trailer which weighs in loaded at 3100 lbs. I've found on relatively level roads the transmission doesn't spend any time searching and I get better mileage. To be honest at that weight the truck even holds gear well going up hill. It is going down where it really helps. So I'm in the boat of don't use it unless the truck is giving signs that you should.

Danielw1

It definetly won't hurt a thing to use it, even if you arent loaded.