The 2012 Rubicons with 4.10's are in good shape for 35's
If my Sport had 4.10's I'd leave it alone...
I am impressed at how well mine pulls with 3.73's and 35's !....auto
As of today I'm installing 4.56's and ARB's
No doubt 4.56's will pull 37's nicely if I ever decide to go bigger..

Gene

 

Every time I read about the 2012's and the Pentastar with the new auto I get a little more depressed.... I guess I'll just have to go buy my JKU something else to make me feel better.

 

I felt the same way I was going to trade my 10 in for a 12 a couple weeks ago then after test driving the 12 I decided to keep mine. Im going to wait to see if the come out with the diesel in the states. They have the grand cherokee with a diesel so the wrangler might be next. If not I guess I will have to buy a hemi

 

Thanks, I haven't looked at them in a long time (since I re-geared) and couldn't remember where they were. Yeah, I see what you mean about O/D.

 

Good to get some validation of the chart data. I'm definitely stoked about the options and believe someone with 4.10s and 35s will reveal just how far you can push things without seriously degrading economy. 4.10s, OD off is the same as 4.88s at cruise speeds, so your findings with 4.56s being in between will definitely help define the chart data moving forward.

 

I am just curious, and i do not have any validation because i have not yet put bigger tires on my 12, but according to this chart i could get away with numerically lower gears on say a 33" tire with an auto trans than with a manual....that just seems funny, even if they are closely geared because dont you get more hp loss through an auto than with a manual, has any one out there put 33's on their 12 with a manual with their stock gears?

 

You have a lock up converter on the automatic which still has a limited amount of slip and you still have slip with a manual and a clutch.

 

I had 4.56 gears installed in my 2012 Sahara unlimited manual. I have to say that it is the perfect setup with 35's. Couldn't be happier with the power. Anything more would be too much.

 

Im running 35's with stock 4.10s on my 2012 and it runs great. The gas mileage could be a bit better. Im getting a consistent 14 mpg.

 

Sounds like I will be installing the 4.56 gears in my 2012 JKU after i throw those 35"s on!!!