We can chat about this when we do our trail run on December 3rd if you want. With the auto, you'll get pretty nice torque off of the 5.13 and you'll be able to move to 37s if you go 5.13. The 4.88 on 35s is probably optimal for overall mpg and decent offroad-ability. Either works really, depends on what you're looking for in terms of flexibility on future tire sizes and/or mileage. 4.88 wouldn't restrict you from 37s, but you'd be slightly undergeared again.