Question on tires

nisryus

Senior member
Sep 11, 2007
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So one of my rear tire got two nails. Since they were within one inch of each other, the auto repair place I visited both techs said they couldn't patch it.

I end up replacing just one tire because they only had one matching tire left for my 2014 Forester. They said the other three still have good thread depth and in good condition. However, because they are almost 9 years old, I should have them replaced as well.

Can I still drive with three old tires for another year before replacing all four at Costco?

The Forester has been mainly in the garage or used for short distance driving for the last 8 years. We only started driving more with it late last year.
 

mindless1

Diamond Member
Aug 11, 2001
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You can keep driving on them but the conservative answer is you should have already replaced them. There's no easy way to predict if a particular tire would've lasted only 8 years, or 9, or 10, etc but they are getting past their retirement age. If you are parking in a garage or other buildings, trees, etc are blocking sunlight, they will age more gracefully due to less UV damage. I would inspect the sidewall and tread for signs of dry rotting and cracking.

I wouldn't drive on them at high speeds, and reduce speed in slippery conditions as the compound has bound to have hardened and lost a fair amount of traction.

It's also more important than ever to keep an eye out for loss of air because with tires that old, they can start to leak and if they leak enough to flex the sidewall too much, a larger crack can develop and lose air much faster, even fast enough to be a problem while driving despite looking fine right before you drove.

Another thing you may already know is a '14 Forester has AWD, yes? This means all tires must be very near the same diameter to minimize extra stress on the AWD system, not just same size on sidewall but due to variances in brands and models and tread wear, need to actually measure nearly the same.

Combine all these factors together and if the new tire you just bought is brand new with full tread depth, then now is the best time to replace the other three with the same make/model/size tire.

Having stated all this, I happen to have a '14 vehicle with AWD and factory tires still on it and wouldn't hesitate driving it around town. It spends > 90% of its time in the garage, only has about 15K mi on it, and the tires look fine... but if I had to replace one, then I'd replace all 4.
 
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pauldun170

Diamond Member
Sep 26, 2011
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So one of my rear tire got two nails. Since they were within one inch of each other, the auto repair place I visited both techs said they couldn't patch it.

I end up replacing just one tire because they only had one matching tire left for my 2014 Forester. They said the other three still have good thread depth and in good condition. However, because they are almost 9 years old, I should have them replaced as well.

Can I still drive with three old tires for another year before replacing all four at Costco?

The Forester has been mainly in the garage or used for short distance driving for the last 8 years. We only started driving more with it late last year.

I think you'll be ok milking it for year if as long as you are mindful that age impacts the compound of the tire. A tire can have plenty of tread life but due to age the tire could be a trainwreck waiting to happen on a slick surfaces or rough pavement.
Stick to speed limits, don't go hauling a car load of sumo wrestlers and take turns well withing reasonable limits. DEFINITELY use safe following distances. Bump the 2 sec rule up to a 3 second rule.
 
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nisryus

Senior member
Sep 11, 2007
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Thx guys. Yeah, the car has been in the garage most of its life, so tires were looking great (sidewall too as I checked)

I am always driving the speed limit, so will be mindful on that. (maybe except when driving between Dallas and Austin on I35.. speed limit is 75 and i drive 70)
 

Dranoche

Senior member
Jul 6, 2009
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An internal Subaru technical bulletin says there shouldn't be more than a 1/4-inch difference in the circumference between the largest and smallest tire, which should translate to about 1/32 to 2/32-inch difference in tread depth assuming same tire and even tread wear. I believe that was originally based on relatively smaller diameter tires from years ago. They still seem to use the same spec. With most modern cars having larger diameter wheels and tires the actual difference in rotational speed from the same difference in circumference is relatively less. You might think that would necessitate an update. Changes in the newer AWD systems could be less tolerant as well, possibly explaining why they stuck with the same spec. Or maybe they're playing it safe for reliability or simplicity. I don't think Subaru has ever discussed it elsewhere. There's nothing in the service manuals discussing it, which only note checking for uneven tread wear, state tread limit for replacing a tire, and indicate that both left and right tires should be replaced at the same time (but not front and back or all 4). Dealers and tire shops regularly quote the 1/4-inch limit. The issue is real, but how severe it may be is something a lot of people question.

The AWD system will treat the change in rotational speed as a slipping wheel, resulting in engagement of the transfer clutches in the differentials when they normally wouldn't such as straight-line cruising. This will result in excessive wear of those clutches. If 3 tires are the same and the 4th is different, you'll end up putting excess wear on both the center differential due to the mismatch between the front and back, and also on either the front or rear differential depending on where the odd tire is located.

Personally I would get the others replaced as soon as possible to avoid any notable differences in wear and because those tires are pretty old, but if you aren't going to be driving it much you're probably fine. Sounds like you don't drive it much if they still have good tread left after 9 years. The tire shop can also shave the 3 new tires if need be to match the 4th.
 
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mindless1

Diamond Member
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^ Or shave this new tire to match the existing three, if it is decided to definitely put off getting new tires and so the one shaved won't be reused, instead buying all 4 in the future. Sometimes the tire deals are on a set of 4 anyway, so with an additional discount it might not save any money to pay to shave 3 down vs just getting a 4th new tire.

Plus if it has a TPMS and the sensor wasn't replaced when this new tire was put on, I'd have the shop pull the tire and replace the TPMS sensor in that wheel while the other 3 are getting new sensors. At its age it is due for new sensors with the new tires.
 
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bigboxes

Lifer
Apr 6, 2002
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Get the road hazard warranty. I don’t think I’ve ever bought a set of tires where it didn’t pay off.
Definitely NO on the "certificates". They don't sell it to be helpful to you. They sell it because it makes them money. What that means is you're more likely to not use it. It's insurance. Insurance is a rip, especially for low priced wear items like tires. If you need a tire for anything that is not covered under your standard warranty, just buy the single tire.

As for the OP, your tires are incredibly old. Sounds like you've probably kept UV from doing damage on them, but that rubber degrades over time. I'd say 6 years would be time to change them, even if you have low mileage.
 

IronWing

No Lifer
Jul 20, 2001
69,045
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Definitely NO on the "certificates". They don't sell it to be helpful to you. They sell it because it makes them money. What that means is you're more likely to not use it. It's insurance. Insurance is a rip, especially for low priced wear items like tires. If you need a tire for anything that is not covered under your standard warranty, just buy the single tire.
As I said, it has always paid off for me to get the certificates.
 

mindless1

Diamond Member
Aug 11, 2001
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Road hazard/etc depends a lot on the situation, the driving environment as well as roads traveled. Here, there are so many potholes that I consider anyone who drives with low profile tires to be an idiot, but maybe not "as" much of one if they have the tire insurance, except that doesn't cover the rim damage.

Personally, I like to destroy the planet with trucks and SUVs that have a fairly good sidewall ratio, and have never needed tire insurance, any flats from road debris were in the tread where I just patched it, but I can accept that random nail/whatever can fall outside the safe to patch zone.

It comes back to the same thing as always, that the insurance is playing odds, and the average person is worse off paying for it, while it is still worthwhile if you have an exceptional case where your risk exceeds the average "enough".
 

BoomerD

No Lifer
Feb 26, 2006
62,899
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Tires "expire" 6 years after they're manufactured... Not when they're sold.
Tires manufactured after 2000 have a 4 digit date code on them SOMEWHERE, showing the week and year they were made.

 

Fenixgoon

Lifer
Jun 30, 2003
31,574
9,956
136
Definitely NO on the "certificates". They don't sell it to be helpful to you. They sell it because it makes them money. What that means is you're more likely to not use it. It's insurance. Insurance is a rip, especially for low priced wear items like tires. If you need a tire for anything that is not covered under your standard warranty, just buy the single tire.

As for the OP, your tires are incredibly old. Sounds like you've probably kept UV from doing damage on them, but that rubber degrades over time. I'd say 6 years would be time to change them, even if you have low mileage.
Maybe tirerack bakes the road hazard into their prices, but I ironically got a flat while helping a friend fix a flat tire of her own - picked up a million nails on the shoulder.

Tire rack covered the $200 to replace my tire (Bridgestone RE-71R)
 

bigboxes

Lifer
Apr 6, 2002
38,598
11,977
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Maybe tirerack bakes the road hazard into their prices, but I ironically got a flat while helping a friend fix a flat tire of her own - picked up a million nails on the shoulder.

Tire rack covered the $200 to replace my tire (Bridgestone RE-71R)
It's statistics. Are you going to believe your brain or your heart? I get anecdotal evidence. Doesn't trump statistics. They charge you this insurance for each tire, not just the one. Plus, when "they" lose they are only out what it cost "them",which is not $200.
 

IronWing

No Lifer
Jul 20, 2001
69,045
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It's statistics. Are you going to believe your brain or your heart? I get anecdotal evidence. Doesn't trump statistics. They charge you this insurance for each tire, not just the one. Plus, when "they" lose they are only out what it cost "them",which is not $200.
It doesn’t matter what it costs them; what matters is what it costs the insured. I drive 5000+ miles/year on gravel and dirt/rock roads so the certificates pay for me.
 

bigboxes

Lifer
Apr 6, 2002
38,598
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It doesn’t matter what it costs them; what matters is what it costs the insured. I drive 5000+ miles/year on gravel and dirt/rock roads so the certificates pay for me.
I used to work in sales. They're all high fiving in the back after the customer leaves.
 

Fenixgoon

Lifer
Jun 30, 2003
31,574
9,956
136
It's statistics. Are you going to believe your brain or your heart? I get anecdotal evidence. Doesn't trump statistics. They charge you this insurance for each tire, not just the one. Plus, when "they" lose they are only out what it cost "them",which is not $200.
Sure, I'm giving them a few bucks, and then their insurer is getting a cut of that.

At the end of the day, if I'm dropping ~1000 on tires, a few bucks extra is worth it.

If the tires were $50 each, then a $10 insurance or whatever it costs is not worth it (and tire rack throws it in for "free" which I assume means it's included in the price of the tire itself)
 

nisryus

Senior member
Sep 11, 2007
739
134
106
Got an appointment and three same brand/model of tires with Discount Tire for later today and did it online. I didn't buy the extra warranty since wife was next to me and said no, when I placed the order.
 
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bigboxes

Lifer
Apr 6, 2002
38,598
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Sure, I'm giving them a few bucks, and then their insurer is getting a cut of that.

At the end of the day, if I'm dropping ~1000 on tires, a few bucks extra is worth it.

If the tires were $50 each, then a $10 insurance or whatever it costs is not worth it (and tire rack throws it in for "free" which I assume means it's included in the price of the tire itself)
I just purchased new tires from Discount Tire on Saturday. They tried to sneak the certificates into the bill without asking my permission. I went back up to the counter and specifically asked if they had charged me for this. They made me see the manager to get a refund. I'm sure they have sales goals that they are supposed to meet.

Afterwards, I go to sit back down. I see my friend that I've known for 35 years. He's getting new tires as well. He says he needs to still pay. I ask him if he's getting the "certificates". He goes, "Insurance for tires? That's a rip off!" Yeah, you gotta separate heart and mind here.
 

repoman0

Diamond Member
Jun 17, 2010
4,479
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I used to work in sales. They're all high fiving in the back after the customer leaves.

The insurance is a flat cost that makes the company money for an average risk profile. He knows his risk profile is well above that average and isn’t going to be charged extra, so the insurance makes sense in that specific case. Can’t just claim statistics when the tire company is using P(warranty claim) in their calculations and Ironwing knows P(warranty claim | 5000 miles driving on rock), a much higher number than the former.

I drive on normal half decent roads so would never purchase it, as do the vast majority of people who do get tricked into purchasing it.
 
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MtnMan

Diamond Member
Jul 27, 2004
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I've used Discount Tires for all of my tire purchases for years, including tires I purchased for my grandson's trucks as a present. My daughter also uses them. Find a better price, and they will beat it, but the last time I priced out tires they were within pennies per tire. Actually 1¢ on each tire.

Grandson replaced tires I had put on his truck when they need replacing several years later. He got over $100 off each tire due to the tread wear guarantee. He was pleasantly surprised, as it saved him over $400.
Daughter ran over a piece of scrap metal that cut the sidewall. Since the tire that matched no longer was being made, they installed a pair of tires, no questions asked.

I have been in the store and overheard other customers getting a new tire free because the old one couldn't be fixed.
 

mindless1

Diamond Member
Aug 11, 2001
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It does depend on the risk but keep in mind that this is AWD. Warranty replacing a tire, means you might still want to shave it down to similar diameter to match the rest, which could be a burden if the place where you get it done, doesn't shave tires. They won't give you 4 new tires when one fails even if the vehicle needs them all very similar diameter, or rolling circumference, however you want to put it.
 

bigboxes

Lifer
Apr 6, 2002
38,598
11,977
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I have been in the store and overheard other customers getting a new tire free because the old one couldn't be fixed.

Yup. I bought three tires this past Saturday. Had bought one 6 months ago. Car was pulling noticeably to the left after they put on the new tires. I went and got it aligned. Nothing changed. Took it back to Discount Tire and told them it was their tires. Turns out it was the 6 months old tire. They replaced it with a new one. Car stopped pulling.
 

waffleironhead

Diamond Member
Aug 10, 2005
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I just looked up what this "certificates" you all were talking about. Just ran a set of tires for my tundra. Discount tire wants and extra $45 per tire for a road hazard? lol.
This is baked into the $20/tire install at sams club.