2017 Sahara JKU tire question

Murseseven

Murseseven

New Member
Joined
Mar 21, 2024
Messages
3
Location
Illinois
Hello. I tried searching for the answer to my question but didn’t find exactly what I was looking for. I did pick up what questions everyone would have for clarification, so I hope I provide what you need:

I have a stock 2017 Sahara JKU we purchased new. It has just over 67k on the factory tires (255/70R18) and I’m getting ready to replace them. I am wanting to keep everything stock other than the tires- I am wanting the look of bigger tires without lifting my jeep or buying new rims. What are the biggest tires I can put on that will not cause me any major issues? The jeep is my daily driver, very minimal off-road unless it’s snowing, and the jeep is geared 3.21.

A coworker had 285/70R17 tires on their jeep and I really like the look of that size, so hoping for something similar. Also, will your recommended size fit on the rear door mount or will I need to buy a different mount?

Any help/recommendations would be appreciated. Pictures would be a great bonus. Thanks all!
 
Have you read this thru?

wranglerjkforum.net

What is the biggest size tire I can fit with no lift on a Jeep Wrangler JK?

One of the most frequently asked questions on this forum is “What's the largest tire I can fit on my stock / unlifted 2007+ Jeep Wrangler JK?”. So, I put this post together so that we can link to whenever this question arises. Preface I'd like to preface this by answering the question in...
wranglerjkforum.net wranglerjkforum.net

3:21 gearing is going to be the biggest drawback. Going larger will kill your torque available. I put 35s on mine and ended up regearing from 3.73 to 4.88s! It now feels seat of the pants normal and had power thruout the power band.
 
  • Like
Reactions: BLACKJKU
That wheel and tire combo are very close to the same size, (yours and your friends) like 1” or so. My .02 cents is, it will me no noticeable difference to the seat of the pants dyno.
 
  • Like
Reactions: BigAL07 and BLACKJKU
Doing a bit of digging on your current tire diameter of 255/70R18 shows about 32" tall with a 10' width. Going up to 285/70r-18 gets you about a 33" tall tire with the same width. Like BlackJKU says, recalibrate for your speedo and transmission to work properly. I'd recommend talking with someone at a good tire store about recommendations. They're pretty experienced with tire size changes.

Going one size up should have very minimal effect on the spare tire mount. A pound or two difference is negligible.

ETA: also do not assume the max inflation pressure is correct. Do a chalk test to determine proper pressures. Google for the video. Pretty simple check, honestly. :)
 
  • Like
Reactions: BLACKJKU
Snowbird Tom said:
285/70R can be had in 18" wheel size. :)
Click to expand...
Yep. I was considering the the OP's question and emphasizing the "rim" aspect. It's kind of irritating to have to decide between returning new rims or new tires because one doesn't fit the other. Been there once, though happily not with my Rubi.
 
  • Like
Reactions: tJKrider
Top Bottom