I've had a 2011 and now a 2012 both JKUR w/ 4.10 gears. The 2011 got better milage due to the fact chrysler changes raised the rpms on the final drive ratio by 700 or so for 2012.
you have to remember that a jeep is as aerodynamic as a brick.... the faster you go the worse your milage, in fact its the first vehicle I've owned that get s the same milage in town as it gets going 75 down the freeway.... yes, I go 75 ( places to go, things to do etc... no time to go 5 under the speed limit...)
2012 JKU Rubicon
Rugged Ridge Front bumper w/storage ends Rugged Ridge 8500 Winch w/ synthetic rope
PIAA ATP off road lights, full light bar, Terraflex leveling kit, Mygig lockpick
just getting started.....