I recently put on a set of 34's on my 2k10 2dr w/ auto. The power loss is OK but I am planing on regearing to 4.88's. How will the new gears affect my mpg's? I do have a superchips to help with everything. I'm getting about 17 mpgs now.

 

when i change from 4.10 to 5.13 with 35 and 5-45RFE and diesel...mpg was better...from 15 mpg to 19 mpg

 

With a 6spd I gained a few mpg's when going from 3:21's with 35's to 4.88 and 37's. You should gain a couple MPG's by regearing because you won't be deep into the throttle trying to gain speed as much. It will be more responsive and gain speed faster.