I'm looking to possibly re-gear(4.88 or 5.13) and put 35's on my jeep. 2 years ago i put the BFG Mud Terrains on my jeep(32's). I noticed immediately that hills are a little harder now and if i put 35's on, it would be severely bogged down. I'm NOT looking for a gear ratio chart, I've seen about a dozen and they don't really help me. What I'm looking for is someone who has an automatic JK, has or has not re-geared, what gears they went with, put on 35's, and how their jeep runs Or Someone who can accurately tell me what gears i should put on my jeep. Thanks in advance!

 

I can only tell you what I have. I put 4.88's in, it's just a hair better than what stock was. Good gas mileage (for a Jeep) keeps the RPM's on the lower side when cruising down the freeway(about 21-2200@70mph). 5.13's is a few hundred more RPM's. Mine is a DD so....

 

I am looking at the same thing. I have 33s now but will move up to 35s when they wear out. Curently have 4:10s with an auto trans.

 

Mine is also my DD. So would 5.13 be too much? According to all the charts, 5.13 would be ideal for 35's. But again, everybody else is telling me otherwise.

 

I don't know which charts you have been looking at, but my opinion is that they are a good resource, and should be checked. (the ones in the faq's at the top of this modified area were designed specifically for the JK, and are divided by engine and transmission - not generic one size fits all charts) You know how it performs now, with your current rpm's/tire size/gear ratio, so having an idea of what the rpm's will be with the new tire size and gear ratio can give a decent comparison.

What it won't tell you is the extra drag you will have from the lift, or from the taller/wider tires, or from the armor and weight you added, or ... The charts also can't figure out what 'your' local terrain is like. Or what 'your' driving style is. Or what 'your' preference or tolerance is. But guess what? Neither can we.

Where do you live? - Altitude? Sea level? Lots of hills? Exceedingly flat terrain?
How do you drive? - All in town? A bunch of crawling offroad? 95% freeway at 80+ mph?
Mods/extra weight? - Completely stock? 6" lift? Heavy bumpers at both ends? A bunch of armor and gear?

There are literally a thousand other threads on this site to read through from people asking the same question. And there has never been a consensus on what one specific ratio is going to be right. (for me, I started with 3.73, then went to 5.13, and then to 5.38. Can I tell you for certain what 'you' will be happiest with? Nope.)