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Should i rotate in the 5th tire?

i have a jeep wrangler and purchased new tires about a year ago. at that time, i was told that i should also replace the spare tire on the back and rotate it in every time i have the tires rotated. this is supposed to extend the overall life of the set of tires. when i took the jeep in for a tire rotation and balance recently, the guy there told me that he does not recommend me doing this because the tire on the back had more tread than the other 4. he measured the tread depth of the spare and said it was about 10mm and the other 4 were about 7 - 7.5mm. i asked if it was dangerous to rotate in the spare and if not, why shouldn’t i do this. he just said he didn’t recommend it but that it wasn’t dangerous to do so. when i picked up my jeep that afternoon, they had not rotated in the spare. i want to take it back in and have them rotate it in, but wanted to check around about the issue first. my husband thinks i should take it in and have it rotated. does anyone here have any thoughts?



i’ve had the tires rotated several times since i bought them and, as far as i know, they’ve always rotated in the spare.

Is that jeep 4WD?

Actually it can be dangerous. In normal driving it is not dangerous, it only becomes dangerous under emergency conditions. Of course that is the very time it can be deadly. Chances are you would never encounter such a problem, but you don’t really want to find out. If you hit the brakes hard and one tyre has more or less grip, it can cause the car to swerve.

If you have some sort of 4WD or AWD, you need to consult your owner’s manual about the advisability of mismatching tyres. In some systems even a small difference in wear on the tyres can cause damage to the drive system.

More bad news: Is that tyre covered on the back? If not it is getting sun damage along with the additional Ozone damage. So even if you never drive on it, you still need to replace it ever few years to make sure it is safe. BTW the same issue occurs to tyres in the trunk, but they age slower.

Good Luck.

I have an '04 Wrangler Rubicon and I rotate all 5 tires, Goodyear MT/Rs. A slight difference in tire diameter should not matter. Wranglers are not AWD, they are part-time 4WD.

i do believe it is 4wd, but i’ve never put it in 4wd. it’s never been off road or in snowy conditions and i wouldn’t even know how to put it in 4wd if i had to.
the tire on the back is not covered, but i normally do a 5 tire rotation every few months, so the same tire is never on the back for too long.

thanks!

What does your owner’s manual say? I’ll bet it says that you can do 5-tire rotations if you’re starting from the same point (i.e. you buy 5 new ones).

If you’ve been doing the rotations on schedule, the spare shouldn’t have significantly more tread than the other ones-- that’s the point! It also extends the time between buying new tires by 25% and prevents the spare from just rotting away on the back of the truck.