Trade it in for one of these.



Lol, J/K. Nice motorhome, BTW. I am sure that a Banks tuner will work on your rig, as long as they use the same motors as the SD trucks. Past that, anything you can do to increase horsepower but not increase fuel burn will increase mileage, so an exhaust would be a good option, too. Lastly, remove anything that you don't use that weighs you down and make sure your tires are inflated properly and your engine serviced in correct intervals.