I have a 2005 Ram CTD 2500 and when in Tow/Haul going up a hill with a fiver @~11000 lbs my transmission downshift, which I expect but, if I should run at 1900 rpm why then does it jump to 2600 to maintain speed. Is it because I have the cruise control set at the speed? Should I disengage the cruise control to allow my mph to drop and stay in the 1900 RPM Range? I have tried coming out of Tow/Haul but it won't until I reach the top of the grade. How do I stay in my RPM Sweet Spot and use Tow/Haul w/cruise control? Newbie on the diesel front that is learning....

 

I do not use cruse control on the hills when pulling a trailer no matter what I drive, It just seems to me that you are more out of control in hilly country especially if it is curvy.

It seems easier on the truck to give it some pedal at the bottom of the hill then as you start losing speed manually shift it to a lower gear and then let it "work" in the higher RPMS this will alow it to run cooler and avoid the constant shifting or hunting of gears and speeds that you will get with your truck doing the thinking for you.