Grandpa / Duroboat,
Mine is a 2001 2500 3/4 ton 8.1 or 454 vortec
LT auto ride.Believe in or not we get 15-17 mpg on the HWY and around 12 in town.That's with BFG Goodrich 285 all-terrains on it.We love this ride.
Good luck,
STRIKE ZONE