I put 35"/12.5 on my JK and they stick out about 1.5-2" past the stock flares, but it's not been a problem. I would suggest a better spare tire carrier than the stock one just because the weight of the bigger tire will mess with the stock tire carrier. I got a Warn rear bumper and tire carrier and I had an issue with squeaking; the tire would vibrate and cause an incessant squeaking that made me nuts. I fit a couple of rubber stops under the tire carrier and it solved the problem. I also heard Warn has a rubber piece you can fit on the carrier to stop the noise as well.

 

To hijack, what kind of other issues can you expect with 35's? The added weight surely means added stress to the drive train. Can the JK handle this, or are we going to need to start looking at drive shafts and such down the road ?

 

That is why I stayed with the 33" purely to find out in the long run (3 plus years) how many drivetrains are startign to go wit bigger tires. I'm sure it will be related to how offten you are offroading/how you drive etc...

 

Please don't take this wrong. I always start with protection first. For me it is Shrockworks rock rails. A yet to be determined oil pan skid, (I still might make my own). And a evap relocation. Only when these are completed, will I even consider taking my JK off road. I'm aiming for the first 5 ft rock ledge to take care of my plastic air dam
Have I ever told you about all the stuff I've broke off road?.........

 

Clear answer, the tailgate will be fine. I give you my word. I've been running my 35x12.50x17 on it with no problems what so ever. And i didn't shim out the rubber stops, and i'm only running 4 and 1/4 backspacing. along with me, a vast number of us here on the forum run the 35 on the spare with no issue, so you'll be fine too.