cweichler105

My dealer has been doing a 4 tire rotation but I'm wanting to start doing it myself and possibly switch to a 5 tire rotation. However, my tires have about 16K miles on them and my spare has 0 miles. They are 32" BFG MT. I've seen similar posts say it's okay to start adding the spare while others believe it may cause issues due to the tire wear difference (16mm vs 11mm). If I had a tire go permanently bad and needing to be replaced, I'd have to add a new tire to the rotation anyway so I figure it should be okay. Let me know your thoughts. My next set will be a different size so not needing to keep the spare. Would rather use it to extend the life of my existing tires. Thanks

JK-Ford

Hey fellow Arki. 5 mm is almost 1/4". That sounds like a lot of ware. And a pretty good differance. I would have to say, wait. Wouldn't want to risk your drive train over a set of tires. As for the "flat" comparison, tire differances has to be considered then too. Big difference between just getting her home. And adding up miles. Price you pay for owning / opperating a 4WD vehicle.

jk_sea

I'm going to lean the opposite direction. Differences in wear and overall tire diameter are more of an issue for AWD vehicles with center differentials and perhaps tires on the same axle with a limited slip differential between them. On a part-time 4-wheel drive system like on your JK, with open differentials, I don't think it would be an issue at all.

I could be really wrong on this one...I absolutely know it's a concern on AWD vehicles but have never had to broach the question on a 4wd/part time vehicle with open diffs.

rob_engineer

I started swapping my spare in at rotations around 19,000 miles. I've now put over 1400 miles on since doing that. Absolutely no issues to worry about.

yo_marc

I'm one who has experienced issues with a new spare mixed into a 4-tire rotation.

The issue is with the JK's stability control. With an over/undersized tire combo on an axle, the stability control will too easily kick in when turning one direction, and not work correctly turning the other direction.

(different sized tires, different rotation rates; the wheel speed sensors are sensitive enough to notice.)

I don't recall exactly how far along a 4-tire rotation I was when I threw in the spare or what the tread depths were. Differences were visibly noticeable, I do remember that. And I believe the front axle may have been more sensitive than the rear.

This was with stock Sahara tires, on a two door, for what it's worth.

k0260

on my lest set of tires, I was only rotating the four, got tired of looking at mu brand new unused spare so I started rotating that in after the other four already had 25% less tread. Worked out fine. Now I rotate all five to get some use out of that nice normally unused spare. Looks better too having nice evenly worn tires all around in stead of a brand new tire sticking off the back.

rvator

What's the difference in a little more tread wear and running a tire 10 psi lower than the others? It will squat more and be shorter. Same thing it will be fine.