You lose the right to ***** about gas mileage, when you buy an Expedition, Lincoln or Cadillac. Inflate the tires to 36-38lbs. It will not sacrifice the ride and will help. Keep the AC or defroster off, when not needed. It costs about a 1/2 mile per gal. Scan the road more, to avoid hard braking. Try Lucas gas treatment, it helps mileage and clean injectors. Ethanol free gas increases mileage 3-5%(thanks Obama for Federal ethanol 'mandate'). Premium will increase it about 5-8%(cafe test done with 90 octane fuel, not gas). Avoid warming it up and extended idling, that lowers your mileage to 0.