will this be ok? they are stock zj rims i think they are 15x7

 

I ran 33 12.50 on my old stock rims for years (15x7) and they work fine.

 

They'll be okay, but the stock back spacing might cause them to rub since the wheel tucks into the fender & the tire is wide.

 

no weird wear or anything?

 

This will depend on the tire. An aggressive mud tire will rub a lot more than an all terrain or street tire due to the side lugs and more square footprint. With the 7" wheel it will make the tire a bit taller and narrower. I'm guessing you have a lift and if your track bars front and rear weren't addressed they will rub on one side.

 

ya ive got a zj with 3.5 inch lift track bars are all set. im running a 31x10.5 with no problem

 

I ran 33 12.50s on 15x7s on my Bronco as well. I was told to keep them a little under inflated to ensure the entire tread made contact and wore correctly.