09 R/T 6 speed with 3.92 and 20 inch RSA allseason tire's. My low has been 17.5 . Average 20 to 21 . And my high driving 55 to 60 on country high way behind some slow traffic was 26.78 mpg with a little city driving thrown in also for 120 miles. I've gotten 24.5 on the interstate doing 85 with cruise on . And some driving in big city traffic .