Originally Posted by f1100turbo
Intersting enough they have two 6% grades leaving town an one being two miles long the ole duramax held 55mph all the way!
Thats pretty good Turbs. Good to know you are getting decent mileage. Did you notice any difference in tranny temps?
I only get about 11mpg but that is about 60 miles of 5-8% grades going over I70 loaded at 55mph towards Moab, and a few miles of almost 9% and tight turns on the back side of Vail pass.
It really is the downhill that is hard IMO!
Semis normally going about 15-25 mph depending on the load.