Had my jeep for 3-4 months now, its a 2007 wrangler x, since I've had it I've lifted it 4" along with 35's and put after market bumpers on it. Looking to start upgrading the mechanics of the jeep such as engine mods and gearing. I had barley any concept of gearing and what the actual options are. Looking for some insight into the gearing and the possibilities! Please post with your knowledge and recommendations ! Also future engine mods the best bang for your buck or what will actually make a significant difference off/on the road !

 

I am looking into prodigy performance for engine mods I have planed for my Jeep .. their website gives great info about the 3.8 liter aka 231

 

With 35" tires, you will probably want to look at regearing to 4.56 or 4.88. If you plan to go to a bigger tire in the future, then look at 5.13s

You will want to also get a programmer that will allow you to correct for the new gears and tire size. I like Diablosport which will also allow you to reflash the factory tune to a performance tune that will give you a little more power and better shifting if you have an auto. This will also let you do other little things like check trouble codes or readjust the tire pressure sensors.

From there, things start to get a little more expensive if you really want to get more power.

 

Open the faq's at the top of this modified area, and check the drivetrain/gears section.

3.8, 35's and 6spd - 4.56 and 4.88 are popular. 5.13 if you don't do a lot of high speed freeway.
3.8, 35's and auto - 5.13. (5.38 is an option if you are thinking of swapping a d44 up front. 4.88 is an option if you live at low alt and drive on flat roads)

ProCal (programmer), Flashpaq and Diablosport (tuners) are popular for recalibrating the speedo, as well as some nifty features.

There are some very long threads on each of these, as well as about a gazillion 'what gears should I get' threads. Should be easy to find all the info you need.