4 of us took my 2012 Supercrew 4wd 3.73 axle 6.5' bed out to Wyoming on an elk & antelope hunt last fall. With a Leer cap to keep everything dry & locked (took a freezer, guns and gear for 7 days of tent life, along with luggage for 2 weeks, fishing gear, etc) a hitch haul on the back with generator and more gear, we averaged over 18 mpg on the way out. We brought back 3 antelope, 2 elk and you couldn't fit a thimble inside that camper it was so full. We looked like the Beverly Hillbillies on the way back. Over the course of a just over 5000K mile trip, our average was 17.1 mpg verified accurate at fill-ups. Mileage was affected the most through Wyoming where the speed limit is 85 and you're fighting a 20-30 mph headwind.
Btw, my tires are far from aggressive, but they do what I need.
