Best I've ever got was running in the flats across Nebraska in my first 02 CC lb7 with 265 on pyo's Hand calculated was 22mpg running 72 mph the whole time. My 07 lbz with the 245's would only get 19mpg even though my display said 23mpg. This lly gets the same as my lbz did with the mods it has. I will agree with MikeL, your drunk if your getting mid 20's for mileage. Either that or your going down hill on a complete tank of fuel.