The milage is 148650 as of this morning, 4WD, Automatic trans, stock gears, I don't know my tire size off hand but they are slightly bigger, I have an AEM Brute Force air intake (3in), 3in turbo back exhaust (Bully Dog), and a Bully Dog Triple Dog Downloader. I'm using Rosella synthetic oil... I got my calculation from the electronic gauge. The trip was a 18 mile trip from New Bern, NC to Cherry Point, NC. With the A/C on I average 21.3. A/C off windows down I got 22.1. Is this really that hard to believe? I change filters every 3,000 miles and oil and filter at another 2,000 miles.