I'm confused.  I thought engaging TOW/HAUL disengaged overdrive.

It does on mine, anyway.  (2004 model)

My understanding is: it is acceptable to have OD engaged while towing as
long as the transmission isn't "hunting".  That is, down-shifting and
then up-shifting repeatedly.

For me, at 7900lbs, I would probably disengage OD to be safe.  And I'd
install a tranny temp gauge and a pyro.

That's my $.02.

Craig C.

that feature is the whole reason I  bought a new 07 2500 RAM.

From what I was told by a lot of friends, the first push to Tow / Haul is an
automatic version of OD off. I was told that the truck would take over and
if it actually could go to overdrive if it felt it was safe, otherwise it
would go to OD off if it felt too much resistance. The second push was if
you wanted to lock out the automatic feature and just leave it in OD off.

I just came back from Banff with my 8200 lb TT. Last week the 04 hemi cost
me 3/4 tank of gas return. As well, it dragged back to 90 KPH on Scott Lake
Hill outside Calgary. This week, the new Cummins came back with 3/4 of a
tank of gas and never slowed down at all on the same hill. It was in TH mode
the whole way.

I still can't get the grin off of my face.

Wayne