Many vehicles can maintain if not improve their Miles Per Gallon through a few simple steps. First, make sure that all of the tires are properly inflated to the standards located inside the driver’s side door. Second, check the wear of your tires so that one is not being overly worn. This can indicate vehicle pulling, and can affect gas mileage. Third, replace your air filter often. When the filter is dirty it makes the engine work harder which causes it to use more gasoline.