Tow haul mode?

You don't have to, but it is advisable. There is a section on this in your owner's manual. It's not just uphill, either, it is every bit as useful, maybe more so, going down hill. Even on Interstates.

What I have read the Tow Haul is to lock up the torque convertor in the transmission. Without going to deep in it basically this reduces the fluid resistance that turns the internal parts that make you move. By eliminating this this will greatly reduce the heat in the transmission. This will reduce the problems associated with excessive heat problems and repair bills. With that being said I engage the button when I start the engine when I am towing. I tow with a 2006 Dodge 2500, 5.9 Cummins R 48 transmission with an added after market Aluminum transmission pan designed for cooling.

Jim and Barb wrote:
What I have read the Tow Haul is to lock up the torque convertor in the transmission. Without going to deep in it basically this reduces the fluid resistance that turns the internal parts that make you move. By eliminating this this will greatly reduce the heat in the transmission. This will reduce the problems associated with excessive heat problems and repair bills. With that being said I engage the button when I start the engine when I am towing. I tow with a 2006 Dodge 2500, 5.9 Cummins R 48 transmission with an added after market Aluminum transmission pan designed for cooling.

My neighbor is pulling a 29' Jayco with his f-350 diesel... it kept tossing him into limp mode...He would pull over , shut it down and restart it and all would be fine,, turns out he was not in tow haul mode.. the tech stated exactly what is above.... It can lock up the converter..

I always (try to) remember to use T/H, even on flat runs. If I forget (and have a couple of times) DW reminds me. LOL I've found in my Chevy D/A it helps to slow you down on the ramps as you exit the freeway. Downshifts a little earlier as you slow - saves on braking some.

For as much as this truck cost me, I will take advantage of every button I can find on it.

(Sorry, couldn't resist.)

ib_leblanc wrote:
Pulling 10,000 lb fifth wheel with f350, 6.4 deisel.. do you have to always use tow haul mode even on flat interstates?

I can't speak for the Fords, but on my Allison, TH mode bumps up the shift points to a higher rpm and locks the torque converter sooner. It also engages auto-downshift. If I'm towing on the flat, I'll turn it off as I approach my target speed (usually around 60 mph) so it will hit OD sooner, then turn it back on to to handle any grades. YMMV...

Lyle

When I'm towing. I set T/H mode and forget it. It does the job it's supposed to on flat, up and down hills, and haven't had any issues.

Whenever I am towing the tow/haul mode is ALWAYS on...

Always on when i tow, gives my Allison higher shift points.

on my Ram tow haul raises the shift points.