So I drive a 2000 Ranger 4.0L V6 4x4 with just over 180k on it. Y'all know how many great things there are about the 4.0, but gas mileage is definitely not one of them! I'm averaging I'd say around 14.7-15 MPG, and the highest I've gotten is around 16.5. This is a bit problematic, since I drive...