My hunting partner thought my trucks milage sucked while pulling this trailer. So I said fine your truck goes on the next trip. Took it on a deer hunt so it never pulled the trailer over the mountains or any mountain passes. So his new Chevy outdoorsman with 5.3 gas engine got 7.7 MPG. I owned a chevy with 5.3 before...no power, this one didn't either, always downshifting and ran 3,000 rpm's most of the time. In hindsight I wish I had a diesel but then a much smaller fuel tank and extra cost of diesel... may have to do some math to see if its worth it