I bought my 96 XJ SE last year and it has 235/75/R15 tires.  I need to replace them and found that the stock tire size should be 215/75R15 (info from the driver door sticker) with 225 listed as optional. I have read , while researching tires, that going from 215/75 to 235/75 is too much of an increase and is unsafe.  My question is this, does going from 215's to 235's require any modifications, and if it does, how can I tell if my XJ has had them? My front tires have uneven wear on the insides and I hear a rubbing sound when I turn and hit the gas.  Could this be the problem?  Thanks.

first thing would be try parking next to a stock xj and look at it, second get dirty and crawl underneath, most lift kits have emblems and or stickers everywhere. i had a 98 xj with 235's that ran smooth as silk no modifcations. if you have inner tire wear you probably need some suspension work, ball joints most likely, or some of the other parts jeep likes to see replaced(at the dealer). but most of these repairs you can do at home if your up to it, and have the basic tools, most of which can be "rented" at an autozone. the rubbing sound could also be due to some suspension failure but it kinda sounds like the tires may be a little too wide or, if you have non-stock rims the backspacing may be incorrect

Thanks for the info.  I do have stock rims.  I think I'm gonna downsize to 225's.  After I get them I'll see where I am with the rubbing sound.  I have a full size spare which is a GY Wrangler in 225.  It was obviously switched out as it has some good wear on it.  What were the OE tires that XJ's came with?  I'm thinking my spare might have OE.  Thanks.  

We had to put a small lift to clear 235/75 on our 01 XJ.  But you could probably squeeze them in there.  

i have a 94 xj sport and i am running 235/70/15. i have not had any problems rubbing or anything.  there is no lift or anything on the jeep.  i would look at the suspension as mentioned above.  

They are probably rubbing something stupid like the fender liner or sway bar bracket. I would do a little looking around and figure it out. XJ's look so much better on bigger tires, it would be a shame to have to downsize just because of a little rub.