Duramax, Allison, Tow-Haul mode advice
We traded the '05 Tahoe in on a new 2013 GMC Sierra 2500HD crew cab with the Durmax diesel, Allison transmission, and HD tow package. We tow a Surveyor Sport 220 that weighs in about 4,400# dry with a...
Forum Discussion
kaydeejay wrote:fly-boy wrote:Please explain why you think that. Higher shift points does not necessarily equate to worse fuel economy if the power being transferred to the road is the same. The engine may be revving higher but at a lower throttle opening.
I would not bother with T/H for a 4400 pound trailer. All it is going to do is decrease your fuel economy.
I have noticed NO difference between T/H on or off as far as economy is concerned.
In fact theoretically economy could be a tad better due to the lack of heat lost in the torque converter.
Without writing a book, in my case, it conserves too much energy. IOW's, when I come down a mountain I may tap my brakes several times and each time I do it downshifts. Then I have to add fuel to keep up with the turtles. Then it downshifts again and I add more fuel...................Downshift, fuel, downshift, fuel, downshift, fuel, downshift, fuel........That adds up.
