My truck started out under 15 mpg new. It's up to 19. 2 average (hand calculated) if I stay under 2000 RPM's with no load. Higher speeds or towing a decent load drops my MPG dramatically into the high to mid 14 MPG range.
6 sp, 4X4, Single Rear Wheel, 3500, 4:10 gears in the back, completely stock 22,000 miles on the truck