As a couple mentioned, with these trucks speed is everything!

Last weekend I drove from home, south of Portland Oregon, to Camano Island Wa, about 265 miles.

I had my camper on the truck but no trailer and drove about 60-65 on the way up. The overhead read 13.5 avg. when we arrived.

We came back Sunday and drove about 55 on mostly secondary roads. When we got home the overhead read 14.7 Avg. Probably would have been around 15.2 if I had reset before heading home.

I've had this truck now for 7 years and 65,000 miles. This type of difference due to speed is normal.

03 4x4 Dually Quad Cab
Cummins, 6 speed, 3.73 gears
Arctic Fox 990 Camper
Total Truck & Camper 13,800 lbs.