2012 w/4.88 and 35"s??
#11
They were not that popular for jeeps with the older drive trains. I know some people like Northridge charge an extra $100 per setup for 4.56.
4.88 and 5.13 are what most old school jeep shops recommend without actually understanding the new 2012+ drive train. Plus he probably stocks them.
#12
He has 3.21's. how would he not see a difference going to 4.56 or 4.88
Yours is a bit different since its an 08. Op has a '12..4.56 will be good, but 4.88 will work and leave room for when he is ready for 37.... Lol a post above shows a '12 with 37's and 4.88 at 3000 rpm @ 70 mph seems a bit high. Maybe not a true 37