Replace 14 year old perfect tires?
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Last edited by Killian_Mörder; Mar 9, 2014 at 06:50 PM.
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From: southeastern Michigan
It would certainly help, but it would be awfully expensive.
Even in a vacuum, though, I think a tire would slowly deteriorate. By that I mean it would slowly crystallize and become stiffer, more brittle, and prone to checking and cracking.
Remember, a tire is made of rubber, which is a polymer in an amorphous state. That's not the lowest energy state, and the material will slowly try to reorient the polymer chains so they become more ordered. When they do that, they become more crystalline and hence stiffer and more brittle.
I'm thinking of a process called "devitrification," which is something commonly exhibited by glass. But it does happen in plastics as well.
http://en.wikipedia.org/wiki/Devitrification
But the vulcanization process applied to tire rubber stops the ability of the polymer chains to reorient, so if this recrystallization process occurs at all, it would be very slow, and I'm guessing that keeping tires away from oxygen (they don't have to be in a vacuum--just store them in an inert environment, such as a nitrogen or argon atmosphere) would go a long way toward preserving them for many years.
Even in a vacuum, though, I think a tire would slowly deteriorate. By that I mean it would slowly crystallize and become stiffer, more brittle, and prone to checking and cracking.
Remember, a tire is made of rubber, which is a polymer in an amorphous state. That's not the lowest energy state, and the material will slowly try to reorient the polymer chains so they become more ordered. When they do that, they become more crystalline and hence stiffer and more brittle.
I'm thinking of a process called "devitrification," which is something commonly exhibited by glass. But it does happen in plastics as well.
http://en.wikipedia.org/wiki/Devitrification
But the vulcanization process applied to tire rubber stops the ability of the polymer chains to reorient, so if this recrystallization process occurs at all, it would be very slow, and I'm guessing that keeping tires away from oxygen (they don't have to be in a vacuum--just store them in an inert environment, such as a nitrogen or argon atmosphere) would go a long way toward preserving them for many years.
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From: Connecticut
It's neither! This is not rocket science. Which part of "it's not a 5-digit number" is not clear? 
As Eric points out, it's elsewhere on the tire, and as discussed earlier, it's possible it's on the other side of the tire as the law requires that the date code be printed on only one side. It's possible that all of your tires were mounted in such a way that the date codes are all on the inboard side. If this is the case, I'm guessing the only way you're going to reasonably see it is to either put the car up on a lift so you can see the inboard side and then spin it until you find the code, or you'll have to remove a tire to look.
But note that it's probably unlikely that all four of your tires, even they were all bought at the same time from the same place, will have the same date code. You'll want to look at all four of them.
Just for yuks, I went out into the garage just now and looked at the date codes on the tires on two of our cars On a set of Firestones I bought in June 2009, two tires had codes 1008 and two had 3408. The 1008 translates to the 10th week of 2008, which means about the middle of March, which means that those tires were 15 months old when I got them. That's kind of annoying, and I might have asked for newer ones at the time had I known enough to look. The other two were made in late August/early September 2008, which is still pretty old for being "new" tires.
On the other car, which we just new bought last month, all four tires have the code 4413, which translates to about the end of October/early November of last year, which is only about four months ago, which isn't so bad.
As Eric points out, it's elsewhere on the tire, and as discussed earlier, it's possible it's on the other side of the tire as the law requires that the date code be printed on only one side. It's possible that all of your tires were mounted in such a way that the date codes are all on the inboard side. If this is the case, I'm guessing the only way you're going to reasonably see it is to either put the car up on a lift so you can see the inboard side and then spin it until you find the code, or you'll have to remove a tire to look.
But note that it's probably unlikely that all four of your tires, even they were all bought at the same time from the same place, will have the same date code. You'll want to look at all four of them.
Just for yuks, I went out into the garage just now and looked at the date codes on the tires on two of our cars On a set of Firestones I bought in June 2009, two tires had codes 1008 and two had 3408. The 1008 translates to the 10th week of 2008, which means about the middle of March, which means that those tires were 15 months old when I got them. That's kind of annoying, and I might have asked for newer ones at the time had I known enough to look. The other two were made in late August/early September 2008, which is still pretty old for being "new" tires.
On the other car, which we just new bought last month, all four tires have the code 4413, which translates to about the end of October/early November of last year, which is only about four months ago, which isn't so bad.
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Just out of curiosity, when did you buy these tires? You know they're no newer than that. Is it possible they're from the '90s? Remember, a tire made before July 2000 will have a three digit date code, not four digit. This was discussed above as well. If you find only a three digit code on that spare tire, it really doesn't matter what the actual date of manufacture is, you know the tire is no newer than 14 years old and should definitely be replaced.
For the most part, date codes on a tire are really only an issue when a tire isn't bought new either because it was bought used or because it was on a used car. Otherwise, it's likely that the tire was made within a year of when it was purchased, so you already have a pretty good idea how old it is.
For the most part, date codes on a tire are really only an issue when a tire isn't bought new either because it was bought used or because it was on a used car. Otherwise, it's likely that the tire was made within a year of when it was purchased, so you already have a pretty good idea how old it is.
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From: Connecticut
All weekend, I was thinking back to when I bought them and I know they are at least 11-12 years old just based on where I lived when I bought them. I remember buying them when I learned that Firestone was going to discontinue them. They sat in the attic for probably a couple of years until the car was ready to receive them. I'm sure I have the receipt at home that I can dig up. It's a shame they stopped making them because they're a great tire.
I'm happy to say that Vintage Tire in Hershey, PA is offering a very good replacement at a fair price. I was even offered a volume discount for buying 2 sets. Coker wanted me to 25 tires before any discount was available and it's literally the exact same tire that they both get from the same manufacturer. I like Coker and have used them in the past but Vintage has the better deal and cheaper shipping due to distance to me so they win the bid! I should be ordering my new wide white walls today or tomorrow most likely.
I'm happy to say that Vintage Tire in Hershey, PA is offering a very good replacement at a fair price. I was even offered a volume discount for buying 2 sets. Coker wanted me to 25 tires before any discount was available and it's literally the exact same tire that they both get from the same manufacturer. I like Coker and have used them in the past but Vintage has the better deal and cheaper shipping due to distance to me so they win the bid! I should be ordering my new wide white walls today or tomorrow most likely.
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Damn shame because these don't even have 1,000 miles on them and look brand new.
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I'm sure I'll have the same experience. Those Firestones I was talking about are on my '67 Delta 88. Between when they were purchased almost 5 years ago and now, I've put about 1300 miles on the car. In four more years, when they'll be 10 years old (after having sat on a shelf for a year before I bought them!) and should be replaced, I'll probably have 2000 to 3000 miles in total on them, and they'll still look brand new.
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Just ordered 8 brand new tires from Universal Vintage Tire. They gave me a pretty good break on buying 2 sets and even ground shipping should have them here tomorrow. Definitely hurts to shell out that much but at least I know they'll all be brand new and safe on both cars for probably the next 10 years. I will now have some nice spares and plenty of extras to make into Wide White Wall tire swings for the little ones
Aside from the cash outlay, I'm really glad I caught this post and can again ride with the comfort of safe tires. Thanks for all the info and tips gang!
Aside from the cash outlay, I'm really glad I caught this post and can again ride with the comfort of safe tires. Thanks for all the info and tips gang!
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One of my friends had a 87 Corvette with original tires. Car has around 20k miles on it, always garaged. Told him to replace the tires..he said they are fine. Looked fine. Told his wife not to get in the car, but she pretty much also ignored me. Few months ago they had a blow out. Just suddenly. No leaks, just bang. Fortunately happened while they were only going 35 mph. Apparently the wife wasn’t too happy. She got a lift home with a friend and left him.
Asked a mechanic about it once too. He said, how much would it cost if I damage the car because of a blow out vs getting new tires. I got new tires.
Asked a mechanic about it once too. He said, how much would it cost if I damage the car because of a blow out vs getting new tires. I got new tires.
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FWIW, I had 4 perfect Goodyear ST's on my car, probably 15 years old. Went to garage last week and one was flat - its had completely disintegrated and the steel beltshad popped out. Glad I wasnt driving when this happened. They showed no wear until that happened
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So I had the first of 2 sets of tires mounted on my red 98 last weekend. I'm very happy that I found this post because we're about to take a long trip with this car in a few weeks and now I know we'll be riding safely on brand new rubber. The best part is that the new tires were only just made this past December so I'm good for quite some time now! Now I just need to touch up the rims, and clean off the blue coating on the white walls. They should look beautiful then! Thanks again for all the info and tips gang.
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Just to close this out, I went with Diamondback tires. They vulcanized a 1" white sidewall over some 275/15 Toyo tires. Took about 2-3 weeks delivered to my door. The new ones are a little taller than my 14 year 270/15's, but I'm hoping I'll get used to the slight difference in ride over time. Smoother, but I'd swear I can feel the ride height difference.
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When I bought our old tent trailer, the tires were badly cracked so I looked at replacing them ... found that the Canadian tire actually had the tires on new rims cheaper than just new rubber .. naturally went with that. Towed it around the maritimes that summer and had a blast ... but I started looking at other people's campers .. Yikes. At the KOA on PEI, an older couple from Texas pulled into the lot next to us and as is usual, a crowd descended to help them set up. Good thing too, as they had a busted lift cable. A couple of guys grabbed their 2x4s and threw the roof up in minutes anyhow. I took the chocks and jacks ... and marveled at their old school white walls .. only to realize they had no outside rubber on the sidewalls left. Lost every bit of sidewall .. I have no idea how the tread stayed put. I told them to call mobile service ... but they opted to drive it to the garage the next day themselves.
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Got me curious and concerned reading this, think I'll get a new tire for my spare, I'm sure it is the original to the car 1955, probably past it's prime buy now. I've never had it on the ground.
....Tedd
....Tedd
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Just to close this out, I went with Diamondback tires. They vulcanized a 1" white sidewall over some 275/15 Toyo tires. Took about 2-3 weeks delivered to my door. The new ones are a little taller than my 14 year 270/15's, but I'm hoping I'll get used to the slight difference in ride over time. Smoother, but I'd swear I can feel the ride height difference.
From the information you've given, the only difference between these two tires is their width, which differs by 5 millimeters (275 versus 270), not the height, and a width difference would not cause the car to ride at a different height. We need to know the aspect ratio.
What's the full tire size designation for the two sets of tires you're talking about. 275/75R15? 275/70R15? We need that number in the middle to know if there is any difference in the height of these two tires. If the middle numbers are the same in both sets, then there is no difference in ride height, and any ride-height difference you think you can feel is all in your head.
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Or X% of 270 and X% of 275.
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He replaced 270/15's with 275/15's. If the original tires were, say, 270/75R15 and the new ones are 275/75R15, the difference in ride height is 3.75 mm. If the originals were 270/70R15 and were replaced with 275/70R15, the difference in height is 3.5 mm.
If both numbers changed, such as replacing 270/75R15 with 275/70R15, the height difference is 4.0 mm.
In any of these cases, assuming we're talking about middle numbers of 70 or 75, the ride height difference is so small that I doubt anyone could tell the difference in a blind test.
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Not even sure they made such animals.
Even A 255/70/15 is quite tall.
I'm gonna go out on a limb & guess he had 225/70/15's originally & now has 225/75/15's (taller).
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From: Shawangunk, NY
I'm very glad I read this thread. I'll be buying new tires. I have a '55 Super 88, any thoughts on where I can find four wheels to fit the car with 225/75R/15 tires?
Roy
Roy
Last edited by Fitti Six; Apr 8, 2014 at 08:37 PM.
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