JimWPB

This has to be the most basic question possible. Somehow, I didn't find it as a sticky or an easy to find preexisting thread.

What is the biggest tire I can put on a stock JK sport 2-door without it rubbing?

Currently I have 32 x 10" tires. They have no problems. Can I go 33"? Can I go 12.5 wide?

If 33 x 12.5 will fit as-is, then I'm done. If I need to add a spacer, then I will need to learn if that also means longer lug nut studs or something like that. I've never used spacers before. If a 12.5" wide tire needs different offset spacing, am I better off buying a different rim, rather than adding spacers? I would be buying rims & tires together anyway.

Thanks,
Jim

resharp001

not going to answer your original question on tire size, but want to clarify that we often say "spacer" when we are referring to "adapters". the most common adapter is going to be 1.5", and that is plenty big to bolt to and cover the factory wheel studs, and then provides you with 5 new wheel studs to mount your wheel to. A 1.5" adapter with the factory wheel is going to net a 4.75" backspace which is plenty to run a 12.5" tire. There's not really an issue running a quality adapter like a Spidertrax. If you removed brake rotors a lot for any reason it does get a little old having another set of lug nuts to remove and retorque, but obviously an economical solution to buying new rims if you're fine with the factory ones. That part is all subjective. If out doing technically challenging wheeling, just better to have proper wheels. for most people an adapter can be fine.

JimWPB

Thanks, when I read "spacer" I envisioned a disk with holes to let the lug nut studs stick through. One set of holes & a new set of studs on an adapter makes perfect sense. I hadn't seen them before.

JimWPB

So far I have used 255/70R18 & 265/75R16 with no problems on stock rims with no spacers. There seems to be just a little more room left. The 18" tires measured about 32 x 10" & were slightly taller than the 16s.

When reprogramming the ECU in Jscan for the different tire sizes, the key switch needs to be on but the engine needs to be off. If the motor is running, all shorts of error codes pop up.

a64pilot

You know I think way back in the day it was done that way, for a spacer, needed longer studs of course.
I go back quite a bit of time being old, but what we called adapters back in the day’s primary purpose was to adapt for different bolt spacing, to put say Chevy wheels on your Mopar or whatever or in Jeeps case I think, but am not sure that older Wranglers may have had a 4.5” bolt spacing where I believe our JK’s are 5”, so to run one of their older wheels we would need an adapter to adapt from 5” to 4.5”.

My experience with them was drag racing in the 70’s, and it was common for them to break, often leading to a wreck so they were outlawed. Maybe they are better now or possibly Jeeps don’t stress them as much, but I remember them breaking so I’ll avoid them myself.

Ref what size tire can I run, I stumbled on this site the other day, probably saw it on a post in this forum, but it allows you to see exactly what this or that size tire will do size wise. Based on that I think Incan run 285 or maybe 295/70 tires, although the 295 might mean a leveling kit and or shimming my turning stops.
https://www.wheel-size.com/calc/