Are unevenly worn tires bad for diffs?

SkylinesSuck

SkylinesSuck

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The shortest and one of the more expensive wheeling trips I've ever done; I took my Jeep into the woods behind my house to help a neighbor pull some half downed trees caught up in other trees down so we could chomp them up. I'm seriously 25' off my driveway and I hear "PFFFT!" and feel the Jeep lean down at the corner. There was what's left of a metal fence post buried in the leaves that decided to make friends with my sidewall.

So $340 later I have a new 285/75r16 Duratrac installed and realized the others are probably 60-70%. Will the small difference in diameter between the tires in the same axle be an issue for my TruTrac limited slip? Mostly I'm thinking of heat cruising at highway speeds. Nothing to worry about or do I need to get another new tire to match it?

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In my area of expertise (large equipment) it is recommended to have no more than a 10% difference in tire diameter. Regardless of open diff, no-spin, or locking.

But a TJ is not a front end loader so there’s that.
If it were me I would spring for another new tire for aesthetic purposes anyway, and the upside being you get another good
spare as a bonus.

Or you could have the new tire ground down to match the others.
Seems kind of silly to waste 30-40% of tread like that but I’ve seen people do it.
 
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$340 for a 285/75r16 Duratrac? :oops: I wouldn't chance running one new tire. Buy 3 more new ones and drop the 3 old used ones off in Charlottesville. I'll put them on my wife's WJ and buy a used matching one. ;) In all seriousness, I've done that many times with zero ill effects. I just didn't post it here to hear the "your diff will explode" comments.
 
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With an open diff, your spider gears will be turning just a little bit all the time. I wouldn't think that will cause much wear, since you're not constantly spinning them hard (which will kill your diff, I've seen it twice on old Camaros — spins out the lube, cooks and breaks the spider pinion shaft).

Like Jerry said, the same should apply to your gear-type LSD, slow differential turning is probably fine. On my clutch-type LSD, I would be worried.
 
Thanks guys, I appreciate the input. I think considering what it cost me, I'm going to dib this trail "Hell's tire killer."

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That is said tree in the background, so as you can see, it's a pretty long trail 🙄
 
Wow that really sucks. :oops: These 1 in a 100 situations are why I always run a 5th wheel and tire and keep it in rotation.
 
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If the difference concerns you, have the new tire shaved to match the other 3. There's 2 way to do this; 1- find a shop with a machine, 2 - find some pavement and apply gas. ;)

 
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I don't know if I posted this before or not but here's my 235/85R16 Duratrac after contacting some unknown object.
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FWIW, the tennis ball wouldn't seal the repair. Maybe I should have shaved the peach fuzz off of it first.
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And for the record that tire being replaced on the wheel I dropped off in early November 2022 was $321.24 while getting all 4 installed with an alignment in June of 2018 was under $1000 at the same shop.
 
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Attention Veterans: GoodYear tires are 25% off for USAA members. They were even recently on special for 30% off around the holidays. I purchased a set of 265/70-17 DuraTracs for my DD last fall for $872 OTD, including mounting, balancing, old tire disposal fees, and 7.5% sales tax.
 
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