I have already ordered a 2 door Rubicon, would like a 3" FT Ultimate lift kit to fit 35" tires. I know with the TJ that driveline mods were needed, especially a SYE kit (which I know isn't needed for the JK). But will I have to extend the driveshaft or add u-joints to it? Or will all I need to do is to purchase the kit and tires? Just trying to budget what it will cost to get it done correctly (gearing will be done at a later time). Thanks.

 

You most likely will be able to get away with running the factory drivelines and without any problems but you're going to be playing on the rocks, I would recommend upgrading at least the rear drive shaft. Currently J.E. Reel is the only one selling heavy duty replacement drivelines and they are available in three different options. Click on the link below for more details:

J.E. Reel Jeep JK Wrangler Drivelines