Just got back from a trip from Phoenix to Laramie WY. I drove my 2012 Ram Laramie 2500 HD 4X4 extended cab short bed with the 6 speed tranny and 5.7 motor and 3.73 gears. I installed a free spin hub kit a few weeks before we left. I drove 2500 miles at either 20 mph or 80-85 mph The best mpg I saw was 17.7 and the worst was 16. I was very happy with the mpg's on this trip. It did drive better with the new hubs. YMMV
