I have a 2008 "X" with 2.5 lift and running the 17" OEM wheels and M/T tires. I want to go to 33 X 12.5 tires on my stock wheels, but I also have the 3:21 gears. What do you recommend I go to on both the front and rear axles?

 

4:10 would be an improvement, 4:56 would probably be ideal if you're never going to go bigger with tires. If 35's are in your future, don't re-gear until you do that (you'll want 4:88's or 5:13's).

 

Start with a search on any of the dozens of threads in the past month on regearing. (the thread titles are a decent indicator of what they're about...)

Both of these are within the last week, and concern, you guessed it, 3.21 gears and 33" tires...

33 tires with 3.21 gears
https://www.jk-forum.com/forums/show...ghlight=regear
Re-gearing opinions...
https://www.jk-forum.com/forums/show...ghlight=regear


Check here for info regarding wheel spacers for running wider tires on your stock rims. Or do a search on wheel spacers for all of those threads.
https://www.jk-forum.com/forums/show...74&postcount=3

 

Ditto....I would stick with what you have, I don't think it will be to painful with 33x12.50's on 3:21 gearing. Some people are even running 35's with this gearing and not complaining to much. When you want to make the jump to 35's or bigger tires.... than I would look at gear upgrading at the same time.