I have a 2010 with 3:73 gears and 35's and it didn't really change that much but then again I live about 300 ft above sea level

 

had the dealer run mine and they said that i have the 3.21 and mine is an auto so you guys are saying to stay away form the 35 if you dont regear not really wanting to do that but was looking at 35 for tires and dont know if it matters its lifted with the rc 3.5

 

Will be lifting my 2012 JK Unlimited in about a month. I also have the stock 3.21 gears with the auto trans. I was under the impression that i would have to re-gear right away, sounds like i will have to try with stock gears, possibly hold off and save my $900.00 the shop wanted for the gear job.

 

I haven't re-programed the speedo yet so I know for a fact that once I get the shift points corrected, the performance will be even better.
You will see that the only "loss" I've seen so far is a loss in power when attempting to pass at speeds over 75mph.
I feel that once my procal arrived that issue will be reduced.

 

I thought someone said 3:21 and and auto isn't possible?

 

I have a 2009 auto and looking at the window sticker, it says 3.21.

 

I have a 2012 now.. Traded my 2011 when I was talked into test driving a 12

 

Does it say that under "standard equipment"? They all said 3.21 and then under "optional equipment" they had the 3.73 listed with the Auto. I do not believe you could get an Auto with 3.21 before 2012.

 

I think its not reccommended based on what I've read in other threads. In my shopping the base models almost always have the 3.21 and the 3.73 is an option and the 4.10 could only be had with the higher option packages. I even tried to order a Sport/auto with 4.10 and was told I had to go with a package to get that. I found a Auto/3.73 Sport. Its a something like $50.00 adder.

 

Not true ~ I have a 2012 Sahara with the 3.6 Auto and 3.21. Metal Cloak Lift, GY Dura tracs which are actually 34". Mounted is 33.75 which is what I programmed. I purchased a Flash Paq from Superchips which allows you to tune based on different octane levels. I started out with the 89 performance tune and now 93. I see a lot of folks talk negative about 3.21 and 35" without knowing all the options. I can tell you with 100% certainty it works and shifts fine. I cruise at 75 at 2200rpms. If you need more info PM and I can share my experience. Just ENSURE you update your tuner via Superchips web site and by doing so, it will allow you to register and ensure you have specific year updates.

Now this doesn't mean I don't plan to re-gear, it just makes it more enjoyable to ride while I save up for my next series of mods. Which are dana 30 re-informant and re-gear