31's
 

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I have been searching the forums on largest tires for a stock suspension xj, and a lot on 235's and 30's. I have 235/75/15 now, but would like to goto 31's. With the 235's I dont have any rubbing issues. I have also cut the front bumper and fender to handle larger tires.

http://img.photobucket.com/albums/v6...88341_3091.jpg

i stuffed 31s on my stock ride height cherokee and cut new grooves in the treads lol, i was kinda rushed and didnt have the time to do the lift. I put 2" spring spacers in the front(pain in the ar$e),and added a leaf in the rear. Cost was about $110 and half a day of getting dirty but i dont rub now unless im really bein harsh with her. I was too late with the lift to save the flares but the local jy had brand new ones. I wouldn't recommend it without the lift first or at the same time. Kinda costly mistake for me since i almost ruined a brand new set of bfg at/ko's. Guess ill be more patient with the 35s i have for my wrangler lol.

Thanks.. So I will start looking at 30's then.

If your fenders are cut you'll be able to fit 31s. The bumper doesn't need to be cut for bigger tires most of us do it for the more rugged look. If you have stock rims you might rub a little but probably only cut all the way. Mine rub and I'm at 5 inches. Its not the height its the width, I have stock rims that's why.