Opinion on AWD tire problem

Posted by slow8033, Apr 10, 2011
Newbie Forum - Beginner DSM modification questions and discussions. Common, repetitive, and general discussions will get dumped here from other tech forums. Unless you're a Probationary member you shouldn't post threads here.

  1. slow8033

    slow8033 Proven Member

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    Ft. Smith, Arkansas
    Last year I got a bad flat on my driver's rear tire. It was ruined so I am forced to replace it. For the winter I put on my snow tires, but now that the weather is warming I have to replace it.

    Being all wheel drive, Do I need to buy 4 all new tires? I have found a replacement tire of the EXACT brand and size. Its tread depth left on it is said to be 7/32. I dont work at a tire shop, so I need opinions from someone who does, or knows the answer to this.

    I measured the tread depth on the ruined tire, and in the middle of the tire it is at about 8/32 or a tad more, and on the edge it is 6/32. Also just from pictures of the online used tire, it seems to look MORE worn than my ruined tire. But according to the measurements they say its not. Granted I dont know the science of measuring a tire's depth...but I dont think its brain surgery. Do you measure from the center or the edge?

    Even if I buy a BRAND NEW exact replacement tire, its going to be taller. So what do I do? The reason for this is brand new the tire is 200-229.00 to replace. The used one I can get for about 50.00.

    With this logic, on an awd car, its bad to have one tire smaller than another because it will spin at different speeds. Thats what I have read on here. But with the same thinking...How in the hell can I turn corners without destroying the differential? tires turn at different speeds all the time. :notgood:
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  2. RT-AWD

    RT-AWD Proven Member

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    Well from what you say they seem to be very close, I don't think there will be a major issue. What you want to make sure of is that the diameter is the same as all the others so mount the tire on the rim and measure from tread to tread. If its extremely close your fine, "extremely close" isn't optimal but, I don't think you'll shred anything.
    #2
  3. 1997gsx4sr

    1997gsx4sr Probationary Member

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    What I observed when I took my car to Less Schwab the other day, they measured at the center of the tire. If I were you, I would rotate the tires. Use them for a couple months. When ready, just get all 4 new tires. Buying used tires won't last you very long. It's up to you bud!
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  4. cliffkemp

    cliffkemp Proven Member

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    carrollton, Georgia
    As long as it is close, it should not be a problem. One thing to do too is to get just 2 new tires and put them on the front as they will bare more weight and wear quicker and just skip a rotation or 2 as long as they are wearing evenly.

    Lastly, the reason you dont want 2 different diameter tires on the car if it is awd, especially if the tires is significantly different is because you will tare up the clutches. they can handle a slight difference in speed between front and back at low speed but, at highway speed, the clutches will overheat and bind like in a truck with just '4 wheel drive' trying to turn on tarmac. It can take low speed issues such as just turning as most of the power goes to the front most of the time anyway but, at faster speeds for an extended amount of time, the awd clutch system will burn up and tare up fairly quickly.
    #4
  5. PieEyedPiper

    PieEyedPiper DSM Wiseman

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    I applaud you for wanting to do it right, however, you're nearing the realm of paranoia. If I read it correctly, your damaged tire averages 7/32 and your replacement just is 7/32. It doesn't get any better than that.

    Full steam ahead.
    #5
  6. cliffkemp

    cliffkemp Proven Member

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    rule of thumb for me is to replace tires in pairs always. On the awd cars I have had, replace the fronts first as I stated above and never a problem. Main thing is to be SOMEWHAT close but, splitting hairs is not needed. If that were the case, a few psi difference would kill the awd system if it were that 'strict' so to speak. If you can get a used one reasonably close, should not be an issue. If you want a new, dependable tire, replace in pairs and put on the front as they will bear more weight to offset the OD. Its not that big of a deal though really.

    He wont tear anything up with that used tire, that is for sure.
    Last edited: Apr 11, 2011
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  7. hoby0316

    hoby0316 Proven Member

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    On awd cars i always recommend changing all four.
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  8. crash89

    crash89 Supporting Member

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    I would at least do two tires. And keep that one used tire and have it mounted on a spare since its not worn much.
    #8
  9. Bud92gsx

    Bud92gsx Supporting Member

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    Your moms house, BC_Canada
    Like stated before I 2nd or 3rd the replace at least two tires..But I would actually suggest geting all 4..
    #9
  10. GSXUAL

    GSXUAL Proven Member

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    As long as the used tire isn't dry rotted,bubbled,plugged or patched a used tire isn't the worst thing but I'd never buy a used one. I mean it's the only thing that touches the ground.
    You would normally replace tires in pairs OR fours. If the two other tires a pretty decent, buy two now, and two down the road some time.
    #10
  11. rlacasse1

    rlacasse1 Proven Member

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    You will be fine replacing just the one as long as it's close to the same diameter, which you say it is.

    There is nothing to worry about.
    #11
  12. bossku69

    bossku69 Probationary Member

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    I've always heard its better to replace all 4 at once, but I hear you with prices.

    I had a tire go on my Tahoe last year and just bought a used one on CL for $60. Tread ware was pretty close and also same brand. I've had it over a year and I'll probably have to replace all 4 by winter time this year, but know that I wont have one weird, low tread tire.

    Likewise, you could sell all 3 online and buy 4 new ones, but dont think you'll get to much for those compared to new ones. Check out Pep Boys for tires, ONLY because if you ask, they will match the buy 3 get 4th free on any tires, not just the crappy $40 ones on the floor.
    #12
  13. GRAVEDIGGER

    GRAVEDIGGER Proven Member

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    The used tire has almost exactly the same amount of tread left as the other three he already has according to the seller. If you can verify the tread depth measurement of the new/used tire is what they say it is by measuring in the middle you should be good to go. There is no need to buy 2 or 4 new tires IF they are all close to the same size. The car won't notice the difference.;)
    #13
  14. gen2allday

    gen2allday Proven Member

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    As long as the tires are the same size and generally the same tread depth you should be fine. What it does is the seals on the diff seals / transfer case seals start to warp which causes leaks due to slipping tires.
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  15. GRAVEDIGGER

    GRAVEDIGGER Proven Member

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    Wow that's some hypothesis you've come up with there.:confused: Where did you come up with that one?
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  16. Viva

    Viva Proven Member

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    See if you can still get the same diameter at a privately owned tire supply
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  17. 95TalonOwner

    95TalonOwner Proven Member

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    I worked at a tires plus and you should be fine with that one tire since it has the same tread depth left on it. Usually on awd you either do all or nothing but in this case it seems that you got lucky and found an exact match to what you had on there.

    You will be fine with that one tire.
    #17
  18. slow8033

    slow8033 Proven Member

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    Ft. Smith, Arkansas
    An update on the tire Saga...

    The tire that I am replacing here is a Firestone Firehawk SZ50, P215/50/zr17. They run about 200.00+ a piece. My replacement tire I luckly found is $27.00. An exact match. Thats why I was asking this question and wanted it to work.

    I went ahead and ordered that 27.00 tire anyway, with the logic of thinking "well, if It turns out I cant run it, at least I have a set of 4 really nice tires I can sell to a 2wd owner". But I really like these tires, they grip well and are AMAZING in the rain. So I called our heros, Mitsubishi Motors themselves.

    After much thumbing through manuals, and fidding about, they gave me the definitive answer that well......they dont know. They have no clue, :hellyeah: no clue at all.

    So I started calling mitsubishi service departments all over the country, and Have come to the conclusion as long as the tire is within 3/32 of an inch, its ok to run it. My replacement is within 1/32 according to the seller. So I just saved 175.00, and my nice set of tires.

    I will measure the tire when it gets here. On the rim, full of air. I will compare the circumfrence to my good tires and make my decision. I'm guessing it will be fine and I will run it.

    I know people think that 1 or 2 32nds of an inch is splitting hairs, and it kinda is, but just for thought, a tire that is 1/32 of an inch smaller than another will in fact rotate 3-4 more times in one mile than the larger tire. It doesnt take much. :thumb:
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  19. xezerax

    xezerax Proven Member

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    Youll be fine replacing the one tire, just put the new tire on the Front, we don't have Viscous front diffs:thumb:
    #19
  20. cliffkemp

    cliffkemp Proven Member

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    it should work. I still recommend replacing 2 at a time or 4 if you can. If you do the 2 in the front, they hold more weight and the side walls will flex a little more due to that. This flex will keep the diameter close to the back since they have less weight on them and will actually be slightly larger in diameter.

    Awd systems are meant to have more play than 4wd. Just dont use donuts for a flat and it will be just fine. :thumb:
    #20
  21. rlacasse1

    rlacasse1 Proven Member

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    WTF

    Are you serious????
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  22. slow8033

    slow8033 Proven Member

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    Ft. Smith, Arkansas
    ^^^^^
    Is this true?

    The replacement tire measures at 6/32, my other tires are at 8/32.
    #22
  23. GRAVEDIGGER

    GRAVEDIGGER Proven Member

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    Yes, the front is an open differential while the rear is not, so put the new (used) tire up front.:)
    #23
  24. slow8033

    slow8033 Proven Member

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    Ft. Smith, Arkansas
    Well I just received the used tire this morning...and measured the circumfrence around the middles. There's only 3/4 of an inch difference. I'm just gonna say Eff It and put it on the front and run it. Thanks for all your help guys! :hellyeah:
    #24
  25. PieEyedPiper

    PieEyedPiper DSM Wiseman

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    I realize you only paid 27.00 but be sure to bi*** if the actual size is not as advertised. People (eBay) LOVE to overrate the depth just enough to tick a guy off when he's under taking a matching process such as this.
    Been there, done that.
    #25

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