Howdy, Lilzen. <img src="/forums/images/graemlins/cheers.gif" alt="" /> I'll let someone with a Wrangler help you with the specifics. In general, if you go too big with your tires, you'll have to re-gear your axles. You're probably correct about 31" tires... that sounds about right. Check out Rubicon Express as a good starting place for lifts.