do i need to use the tow haul all the time even on flat freeway? the trailer is 1400 lbs and car 3500lbs almost 5000lbs which aint much for the hemi. i ask because it raises rpms and i am doing a 2400 mile trip to washington and i am trying to wach gas milage. i understand hils and passes in the rockys i will need to use but what about the flat?

 

I would personally say that if it is going into overdrive, and lock-up there should be no need to use tow/haul. If the convertor fighting to stay locked up, then I would recommend using it.

 

AT CRUISING SPEED NO NEED FOR TOW/HAUL

 

I don't know about the 06 but on my 04, with the Tow/Haul on, it will settle down to OD rpm's while on the highway, but will leave the TC locked up longer and will not downshift until later.

When I tow my parents' boat, I always use the Tow/Haul mode.

 

If its not shifting around for gears and the road is flat then I would keep it in OD. If it gets hilly and you feel the truck searching for the right gear alot then use the Tow mode.