I may be off a bit, but those that think realistically that your going to get great mileage with a 7000+lb truck with aerodynamics like a barn are crazy...it aint gonna happen. Sure I can go get 25mpg; coasting downhill. Anybody getting 20+ is cruise set about 65 maybe a little more and thats steading driving on an interstate. I dont for a second believe the guys that say they have ____ hp and get 20+ in mixed driving. The odds of that are very slim. Want good mileage? Go get a car with better aero and keep your foot out of it...not pointing fingers, just my opinion