Thinking of installing a full time roof rack and moving the spare from the rear mount to the roof.

Anyone done this and found out how it changes gas mileage?

I would think minimal compared to other vehicles because the H2 is already heavy and not so aerodynamic. Hoping this is the case.

 

I have a roof rack and I moved my spare from the trunk to the roof. I have not noticed a big difference in gas mileage. But I never cared much about the gas mileage, it's my big boy toy to have fun with. Like you said, since the H2 is already like a massive refrigerator on wheels I doubt a roof rack makes much of a hit on mileage.

 

I never saw in change in gas mileage after installing my roof rack. Although like the above poster, I never really cared about MPG driving such a large box on wheels.