If you get a bed cover, that will increase your mileage anywhere from 3-7 percent.

 

Diablo on the tuner.
I am averaging about 15.7mpg with my 2wd at about 75%hwy/25%city at 65 to 75mph. about 1/2 of the hwy miles are kinda hilly and is killing my average. On a flatter highway test, I can get about 19 to 20mpg @ a steady 65mph.

 

I have an folding soft cover on my truck. It is made by Rugged Cover, folds into three sections, uses levers to anchor it down in all four corners (with safety clips in the rear). Whether I am installing it or taking it out it takes about 5 min with one person. I don't have a picture but I like it a lot.

 

I found a picture of the levers (right) and the safety connector (left).

 

not sure about the mileage never really checked it. I drive my truck like i stole it, but when I do drive it nice and easy (which isnt very often) i normally get 15 to 15.5. I have order the predator tuner, once i get back im gonna plug it in. The only down fall with the cover I got is it is heavy and takes two people to get it on and off.

 

Thanks for the help everybody!!