I have seen a best of 35.6 with ours and 32 is pretty typical highway driving. Great little work horse. Tows our 23 foot camper easier than our 3/4 ton Suburban with 4.10's and the 6.0. Saw 15.6mpg towing our 23' camper on our last mountain bike trip to Copper Harbor while the Burb sees 8 to 9 tops towing it. Towing our 22 foot sailboat it gets around 22mpg. Friggen love this truck. I know the ZR2 is immensely capable offroad but the LT and Z71 are pretty competent at pretty much everything.