Yeah, that's what I've managed with my V-10 in the past. Don't see it now, but used to see 13-14 all the time with a one hour, 40-50 mph commute I used to have. What really amazed me was when my truck averaged 14.5 mpg comming across the (flat) central US while loaded down and towing a loaded 2-place snowmobile trailer. The reason? My wife was driving it following me in an overloaded Ryder rental truck that wouldn't do over 60 mph.
Matt
99 V-10 Super Duty, Super Cab 4x4