This may sound really dumb but what exactly does tow-haul do? I have an 07 6.7 with the 6 speed auto and have used it a few times but I'm not really sure what it does.

 

Not positive, but I believe it changes the shift points per engine rpm and wheel speed. probably allows higherengine rpmbeforeshifting.have you noticed this at all with it engaged?

 

On my 06 1500 not only did it change the shift points, but it also would down shift to give a little engine braking when you applied the brakes on the truck.

 

That is a pretty decent setup you got going there, I like it!![sm=insomnia.gif]

 

OPERATION
At key-on, overdrive operation is allowed. Pressing the switch once enables Tow/Haul mode and the Tow/Haul lamp will be illuminated. In Tow/Haul mode, 6th gear is disabled and 4-5 upshifts are delayed. Shifts into 5th gear are still allowed under steady cruise conditions. Closed throttle downshifts (for improved engine braking) may occur during steady braking maneuvers. Pressing the switch a second time enables OD Off mode, where all 5th and 6th gear operation is inhibited. Pressing the switch a third time restores normal operation. Normal operation is always the default at start-up; the switch must be pressed after each key start if Tow/Haul mode is desired.

 

I know on the 48re's it would lock up the TC sooner, I would imagine it would do the same on the 68re's as well.

 

Thanks for the answers. Tow Haul does not disable 6th gear in the auto it still works just fine.

The only thing I have really noticed so far is that it downshifts really hard when using the exhaust break. Up shifts don't seen to be really any different.

Unfortunately the owners manual doesn't really tell you squat.

 

so ya running the tow/haul and exhuast brake with out really any problems huh? is that with all six gears?

 

so with tow/haul on would regular driving without trailer give better mileage being that it changes the shift points to higher rpms? or are my crazy for thinking that[:-]?!?!

 

Yeah Big Blue it works just fine in all 6 gears. What I find is that when I'm in tow haul and whether or not I have the exaust brake on when your speed drops below a certain level the tranny shifts down this happens all the way down to 1st. This doesn't happen when tow haul is off. It's like you are downshifting it manually only it is automatic.