I have a 08 jeep wrangler Sahara. I am looming to upgrade the gearing ratio on it because I basically have zero power. I am running 36-12.50 inch tires what is the best gearing change I can do to acquire MORE torque?

 

I have 5.13's and run 35" general grabbers I say they are about perfect and leave me the choice of running 37's if I decide to

 

4.88 for a manual

5.13/5.38's for an auto.

Saw on Summit there make 5.38's for a dana 30, no 5.13's but could have missed it.

The only thing that really brings on the power for our mini-van enhanced power plants is a super charger. Am running 5.38's with my 37's and its still a dog up any paved hills.

 

4.88

Anything higher (numerically) will cause the pinion gear to be VERY small for a D30. This makes your weak link the R&P and this is a crappy trail break.

 

Agreed. I waited until I found a front D44 and I'm going 4.88 now. I wasn't going to push the d30 past 4.56

 

The chart might give you some help.

With the 3.8
http://farm3.static.flickr.com/2447/...f4f380cb_b.jpg

With the 3.6
https://www.jk-forum.com/forums/uplo...o-chart-12.jpg

Edit: Both are borrowed for the interwebs

 

I have a 2011 JKU auto and went with 4.88 gears. Definitely more torque. I was told by shop going any higher would not be necessary.