Peacock
Addicted to ArboristSite
I get 22 mpg in my 1/2 ton 4x4 extended cab pick-up. Of course, it runs on 4 cylinders when cruising. It has a 5.3 liter motor. Weighed down with wood and pulling a loaded 5x10 trailer loaded, more like 16 mpg.
Hmm...the wife's 4x4 5.3L Avalanche has never gotten over 19mpg. It's got the same engine as your's.
Must be the extra weight of the Avy. It's about 6k unloaded.