I have owned 03, 05, and 07 F150's, the last a 4x4
four door with a triton 5.4, great truck, never had a problem in the 130,000 miles I put on it. It had 16 inch rims as part of a factory trim package and the best, the absolute BEST I was ever able to squeeze out of it was 15.5 MPG
highway, on multiple 1,000 mile plus trips.
It was a company vehicle with (thankfully) company fuel, and when gas was at its peak the monthly lease payment was 545.00, and the monthly fuel bill was 800+, around town the thing was an absolute pig, 8-12 in heavy city driving, with AC
Looked into it and it was normal, just a horribly inneficient motor, other than that, great truck.