sounds like your lovin that f250
97 yamaha yzf1000 (sportbike)-65mpg is my best cruisin on the highway, normal is 45-50mpg.
1979 k5 blazer-16mpg mixed, no overdrive with a 327 gasser.
1995 gmc yukon turbo-diesel (used to be my dads, mine as of july 3rd) 25mpg at 70mph, air intake upgrade.
Gonna start driving the toy to work though I think. I get about 18mpg mixed with it, and seeing as diesel is about .70 more, Its more economical at the moment