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Do I need a new tire?

  1. May 21, 2014 #1
    When I got an oil change at my car dealership, I was told that my car needed new tires. I've had them since I got the car 40,000 miles ago. They said that they were "in the red", which I took as meaning they needed to be changed immediately. Well, when I got the car home, I looked at the tires and they all looked fine to me. My front driver's side tire seemed worn more than the others, though. I guess that's because of 99% of the time, it's just me in the car.
    Just by looking at the pictures, would you say they'd need to be changed? I could understand replacing my front driver's side tire, because that one looks pretty worn, but I see no justification in replacing all of them just because one is worn a lot.
    The first picture is my front passenger's side tire (All the tires basically look like this except for the front driver's side tire), and the second picture is my front driver's side tire.
    Thanks.
     

    Attached Files:

  2. jcsd
  3. May 21, 2014 #2
    I had to switch after 50 000 km so not even 40 000 miles, I am pretty sure you had better do it and all of them. Reasons? Less hassle for yourself.
     
  4. May 21, 2014 #3

    Borg

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    Can't tell from the pictures but look to see if the wear bars are flush with the remaining tread. If you don't have wear bars, you can use the penny test in the link below.

    Tire Tread Tests
     
  5. May 21, 2014 #4

    dlgoff

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    The circled tread does look to be nearly gone. Since the wear is worst on one side, it could be due to it's wheel being misaligned. If you get new tires, be sure to get a wheel alignment, with the new tires mounted, or the new set will wear out too soon again.

    attachment.php?attachmentid=69956&stc=1&d=1400712375.jpg
     

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  6. May 21, 2014 #5

    AlephZero

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    You want to left and right tires on each axle to have the same amount of tread (unless you drive like a 90-year-old!), so you normally replace them in pairs unless a nearly-new tire gets damaged for some reason.

    It's not a good idea to have new tires on one axle and very worn ones on the other, If you get into an emergency situation you don't want one end of the car to be more skid-prone than the other end!

    Of course if you still have a new spare tire, you can keep the best of the worn ones as a spare.

    FWIW I get about 30,000 to 35,000 miles from the front tires on a front wheel drive car (which is about the same as lendav_rott) and maybe 50,000 from the rear. Rear tires sometimes die from old age (the sidewalls start to crack or bulge) or accidental damage rather than the tread wearing down.

    The mileage you get depends on the price of the tire (at least in the UK). "Budget" tires might only last 15,000 miles not 30,000, so they all cost about the same per mile in the long run.
     
    Last edited: May 21, 2014
  7. May 21, 2014 #6

    russ_watters

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    The rule of thumb is if you stick a penny in head-first and can see all of Abe's head, the tread is too thin. There is a good reason to replace them before they are completely bald: if you wait to replace the tires after they are completely bald, you risk replacing them after you crash your car.

    Also, you need to start rotating your tires so they wear evenly.
     
  8. May 21, 2014 #7

    strangerep

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    I guess the regulations are vary in different parts of the world. In mine, an emergency braking test is required before a vehicle can be re-registered -- roughly, in what distance does the vehicle stop from a specified speed with brakes applied as hard as possible.

    Even so, the standards are too weak (imho). I have a very steep driveway which becomes slippery and dangerous in the wet. If my wheels start to spin while driving up in the rain, I know from experience that it's time to get new tyres on the drive wheels. Curiously, this seems to be almost independent of how many kms the tyres have done (I do very few kms, and the car is always garaged). The tread on the tyres still looks fine. There seems to be some kind of aging process occurring in the rubber -- simply being 2-3 years old means it doesn't grip as well. New tyres fix the problem immediately.

    This makes me suspect that most people are actually driving around on unsafe tyres. I.e., if they had to jam on the brakes really hard, their car would take too long to stop. Taxis are the worst: sometimes they try to come up my driveway instead of waiting at the bottom, but they don't even make it halfway -- in the dry(!).
     
  9. May 21, 2014 #8

    AlephZero

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    I suppose you don't mean "completely bald" literally. I don't know the US regulations, but in the UK the minimum legal requirement is 1.6mm (1/16 inch) of tread in a continuous band covering 3/4 of the tire width in contact with the road and the full circumference.

    AFAIK the tire tread wear indicators on UK tires are 2mm deep to give a bit of tolerance over the 1.6mm limit. I don't know if tread wear indicators on tires are a legal requirement in the UK but I haven't seen a car tire without them for decades.

    The maximum penalties for illegal tires in the UK are a £2500 fine and 3 penalty points on your driving license per tire.
     
  10. May 21, 2014 #9

    lisab

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    What I find troubling is that your tires are wearing unevenly. Like Russ mentioned, they need to be rotated to function properly.

    From the pics you posted, the second one has a band of baldness that the first one doesn't have. That may have been caused by having low pressure for a long time. Or maybe they aren't balanced right, or maybe your car has a warped chassis due to a previous accident? Regardless, it's dangerous to drive on that tire much longer. If I were you I'd get new tires.

    If you can't afford it now, put the bald ones on the back. If you're going to have a blow-out, it's much safer to get it on the back than on the front, especially at high speeds.

    Oh and you might want to avoid high speeds until you get safe tires.

    Band of Baldness would be an awesome name for a punk rock group, IMO.
     
  11. May 21, 2014 #10

    russ_watters

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    I meant completely bald. I've seen tires on friends cars that had essentially zero tread.

    Not all states do inspections (auto regulations come from the states) and even then they are at best annual, so there is no way the government can know for sure how much tread is on your tires -- and those tires in the OP looked pretty thin.

    And I've been there myself: I occasionally won't be paying attention and have been shocked at how thin the tread is.
     
  12. May 21, 2014 #11

    russ_watters

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    That's re-assuring. In the northeast US, we had one of the coldest and snowiest winters on record this year. My car has low profile tires (my girlfriend thinks I want to be a gangsta, but I just like the way they look and handle) and I destroyed both front tires and one rim in three days in March, when the snow melted and the potholes were exposed. I was on my way home from returning a loaner when I blew the second.

    The second tire didn't actually explode (neither did, actually), it just bulged-out the sidewall like an aneurysm. But there was no way I was going to keep driving on it - tires explode when they are under stress, which means they do it when you need them most: high speed, a sharp corner, heavy braking, etc. It's just too dangerous to risk it. Reiterate for emphasis:
    My gangsta tires are absurdly expensive, but if the OP has normal tires, it really shouldn't be much money to replace them: less than two tanks of gas. Just suck it up and do it.

    That sounds like my forehead: I'm in.
     
  13. May 21, 2014 #12
    Most tire retailers and auto dealerships now insist that, if only two tires are purchased, they must both go on the rear. I really questioned that until I saw the video below.

    https://www.youtube.com/watch?v=--Hb5kQCaTg&feature=youtu.be

    I find Discount Tire's 6 months to pay and 0% interest deal works for me. On the other hand if you miss a payment the interest rate jumps up to about 27%.:cry:
     
    Last edited: May 21, 2014
  14. May 21, 2014 #13

    russ_watters

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    That makes sense except for one problem they don't address: if the tires with the better tread are on the back, won't that just result in a continuing divergence in tire wear? Deeper tread is more important for back tires, but front tires wear faster. They don't address that issue and I'd be curious to know how to resolve it.
     
  15. May 22, 2014 #14

    dlgoff

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    Probably would depend on which wheels are doing the driving and/or the operator. :devil:


    http://cdn.carthrottle.com/wp-content/uploads/2012/09/Burnout_600.jpg
     
  16. May 22, 2014 #15

    DrClaude

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    Why don't you rotate tires?
     
  17. May 22, 2014 #16

    Borek

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    To add to the video what edward already posted: few years ago we had an early snow in Warsaw. My neighbor started replacing summer tires, and he replaced the front ones, but for some reason could not complete the operation, so he got on the move with winter tires on the front and summer tires on the back. After about 5 miles he did 360 when changing the lines on a three line bridge across Wisła river and hit some other car, luckily nothing happened to him nor other people.

    And his driving skills are way above average, he did some rally driving in the past.

    Tires with a better grip on the back. Always.
     
  18. May 22, 2014 #17
    Don't you have little 'knobs' inside the center thread?
    Over here when this knobs are level with the surface you should get new tires. Although I probably wouldn't check them often enough.
     
  19. May 22, 2014 #18

    OmCheeto

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    I believe they are called wear bars. {edit} I see Borg mentioned that yesterday. Oops. {/edit}

    http://news.preferredautogroup.com/wp-content/uploads/2013/04/tire_wear_bars-001.jpg [Broken]​
    Over here, we do to.
    Ditto.
     
    Last edited by a moderator: May 6, 2017
  20. May 22, 2014 #19
    I think that it is a liability issue more than anything. I don't think that they care about the fronts wearing faster. From my own experience I have noticed that it can also be a sales gimmick. A salesman once told me in regards to the situation: "Now you are going to have worn tires on the front drive wheels."

    They told my daughter that they couldn't put the rear tires on the front because one was worn more than the other and it could cause damage to the differential. This can be a valid point, but she sent me pictures of the tires and I told her how to measure the tread. The tires were fine for the front. It was all sales hype.
     
  21. May 22, 2014 #20
    Thanks for the advice. I guess I'll just go ahead and get them all changed. I've driven 40k miles on them, so even if I don't have to change them all now, they're probably nearing the end of their life, right?
    When I got my oil changed at my car dealership, they said they had a deal where I could replace all 4 tires and they would balance them and do an alignment, all for the low low price of $550. Is that too much? Everywhere I look, it seems like I'm gonna have to pay about $100 for each tire, and I'm not sure how much an alignment is. I guess I'll just call each car store and see who has the best price.
     
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