I have a leSharo RV that I want to get better mileage. It has been converted to a Buick 3.8 v6 and a a 4t60 transmission with a 2.87 Final drive ratio. It has 1630 RPM at 65 mph. It has 205/85R14 C tires at 60 psi and weights 5500 lbs, 6500 lbs gross. It has only a 15 gal fuel tank. Last time I drove it it got between 15 and 17 mpg. Today I blocked off around the radiator with foam and put a belly pan from the front bumper to the front tires.
It looks like this without the roof mounted AC unit.
