Just went through my first tank of fuel and filled up yesterday. I got a hand calculated average of 15.5mpg I'm really happy with that considering I've done alot of full throttle blasts to 60, alot of stop and go city driving and a few longer distance drives. The truck is a 1500 4x4 CC Hemi with right around 400 miles on it. It also has 20" wheels and 3.55 gears. Also all of my previous Hemi's got alot better mileage after about 10,000 miles. I'm going to be taking a 600+ mile round trip easter weekend covering mostly interstate with some small rolling hills. I will report back then with the mileage I get.