I have a 6.2, F350 work truck that I really like. It spends quite a bit of time running back and forth on Interstate 70 near the Eisenhauer tunnel and because of that it spends quite a bit of time in the 4,000 RPM range where it makes plenty of power and sounds wonderful...:). Gas mileage? 10 mpg's or so mixed but the truck is loaded with a couple thousand pounds, spends a lot of time at higher RPM's and is new with only 2,000 miles on it so this isn't a fair representation of what the truck would get under normal use.