I have had my 2013 Laramie for a week. It has the Hemi with 8speed, air ride 3.92 gears, posi, 4X4, 8.4an bunch of other stuff. I am at 500 miles of mixed driving and to date am averaging 18.2 mpg. Love the truck! Unreal how much better it runs and handles with the 8speed and air ride