I've got a 2000 F-150 (reg. cab short bed) 2WD with the 4.6 liter V8 & a 3.55 rear end... At 55 mph. it gets 20 mpg. (EPA estimate 17) Covered bed helps. That little engine will PULL.
(and it's going strong after 215,000 miles.) My girlfriends Focus got 25 mpg + ... until she hit 95,000 miles... Then she had to spend nearly $3000 on electronics and fuel injection repairs. I can buy a lot of gas for $3000. The Toyota suggestion was a good one... If I weren't 6' 3" and 270 lbs. I'd get a Tacoma.