[shermanator2]

I have a 2006 F-350 SRW 4WD with the 6.8L V-10 that just turned 200k miles. Mine is 6 speed manual trans with 4.10 gears.

Unloaded freeway cruising it will get close to 12mpg. However, load it up with a trailer and it really loves to suck the gas. The engine needs RPM to make power. Not much in the low end torque department that would be expected in a truck motor.

I pull an 24' X 8-1/2' enclosed car trailer weighing about 9000 lbs loaded. I drive I-70 over the rocky mountains. It will make the power to climb the hills without being that slow guy, but I wind the piss out of it to do that. Up hill or with a head wind I think I get down to around 4MPG.