WJ spare tier bin.
 

I originally posted this in the modified tech discussion because I plan on putting the JK 17 inch wheels on it, but releasing now that the WJ could be optioned with 17s stock it became irrelevant for that, making my question in a grey area between stock and modified. does any one know what the largest tire I can put on and still be able to use the factory spare location?

A 245 width will just fit, but the overall diameter has to be the same as the stock tire. This means probably a 60 profile tire. Check with tire dealer's web sites. They should be able to tell you the overall diameter. I think mine are 29.5" (245/70R16)