I got ~8 mpg coming across ND and MT pulling a horse trailer one time so assume it is still similar. This was with my 2000 3/4 ton with the 4:10 gears and 6.0 engine. I haul hay ~ once a year and then the horses. Other than that I rarely haul heavy. The reason I am more interested in a gas engine. However, I sure liked the power a friend had when hauling with his diesel.
