"NEW" tire age/ build date

[glennc]

Mrsilv I agree with you as far as the customer service angle of your post goes. However I believe your quotes are really only relevant to tires that have already been put into service. There may be a misconception here in that there are two separate anti-aging mechanisms: the preservative put on a new tire that is worn off in the first few miles of use, and anti-aging compounds actually mixed into the tire rubber that are continually distributed throughout rubber as the tire flexes.

I am sure that the first quote, for example, refers to six years from the time the tire is put in service, as 1) the customer is not expected to be aware of the manufacture date, and 2) there would I assume be a separate tire-manufacturer shelf life stating how old the tire could be before it is sold. So the official DiamlerChrysler position was probably that the tire would be safe if put into service at the end of its shelf life and used for six years, and I most likely that is still an exceedingly conservative approach since that is what manufacturers MUST take towards tire issues these days.

If you use common sense, use your vehicles regularly and keep them in a garage and away from ozone sources, you could safely go much more than six years in use. If you have tires on a car that is parked outside with full sun exposure in a hot climate on a vehicle that you rarely drive, then that is what the six year recommendation is made for. In fact it seems remarkable that under that kind of environmental attack the manufacturers would still stand behind their tires for six years: it shows just how resistant to degradation modern tires must be.

When it comes to new tires, though, I haven't seen any evidence, caution, statement etc, here or elsewhere, that a tire isn't essentially as good as new up to the last day of the manufacturer's shelf life it properly stored, and probably much longer.

Instead I see people taking already conservative recommendations, inappropriately applying them, and then having a fit when reasonable people don't fall in line with their flawed conclusions.

 

[Quattro Pete]

Originally Posted By: glennc
There is a lot of alarmist nonsense in my opinion that is making people freak out about perfectly good new tires.

Call it what you want. I am speaking from experience with my winter tires up north (winter is where the negatives of old rubber can be easily observed). By the 4th winter, the snow performance of my Michelin Pilot Alpins deteriorated greatly, despite having more than 50% of tread remaining and despite the tires being stored indoors (when not in use). I attribute it to the fact that the rubber had hardened over time and thus compromised snow traction.

So, if the deterioration happens so quickly, would I want to buy tires that were sitting somewhere for 3 years and on top of that pay for them as if they were new? Heck no! The best 3 years of these tires' life have already passed... sitting on a shelf.

Granted, Russell's tires are not winter tires, but they're all-season tires which he will most likely use during winter. If he finds himself driving on them in the snow, he should be extra cautious.

 

[glennc]

Pete you are comparing an in-use tire that has been heat-cycled hundreds of times and partially worn to a preservative-coated, stored, un-used tire.

I have to admit that all the references I have been able to find indicate that there is actually not a manufacturer stated shelf life for tires and that indeed most authorities do recommend replacing tires by about ten years from the original manufacture date.

I have also learned that this is an area of hot debate in the industry itself, partly because storage conditions are highly variable and an improperly stored tire can degrade within several years even if new. Fair enough.

My own experience comes from having old motorcycles, which usually have old tires on them. I have motorcycles in my garage right now that have tires between ten and twenty years old on them which I would not hesitate to take up our local Lookout Mountain right now at any pace the bike is capable of. My SR500, for example, has a tire coded "518," and since the bike is an '81 and the tire was a model no longer available in '98, the tire was made in 1988. The tire has fat dark bands and heavy wear on either side from hard use on our local twisty roads, and scrapes on its footpegs, and I can tell you that its front tire had absolutely solid traction at the limit the last time I used it that way.

Maybe the most remarkable example I had was a '73 Honda XL350, which had low miles on the original trials-pattern tires. When I rode that bike around those same roads I was very cautious at first because of both the pattern and age of the tires, but as I kept easing up the pace I eventually found myself astonished at their level of grip. That bike felt like it could lean over until the handlebars just about dragged on the pavement and the tires didn't even squiggle. This was maybe two years ago now and I still wonder how a pair of old dirt/street tires could work that well. It was beautiful.

My XT350, by contrast, has the original front Bridgestone ('92 - on a '95 model year bike!) and an aftermarket rear Pirelli ('01), and the tires will begin to lose traction predictably at relatively modest lean angles, just as new dual-sport style tires tend to do.

My point is that the degradation in tires seems to me to be less than vast even over decades when they have been stored appropriately. Compared to examples like these, it seems to me that an un-used tire, stored, still coated with factory preservative, will be so little affected after three years that the effects will be essentially nil.

I realize this goes against the current conventional wisdom, and I suppose I don't expect that to change. I do believe that it is the product of aggressive trail lawyers, conservative corporate lawyers, and a bias towards preventing rare worst-case scenarios rather than advising for tires subjected to ordinary care and use. Don't forget that when a tire company recommends a conservative life span they can wind up selling more tires, so it is sort of a win-win approach for them to take. I suspect that much of the current tire-manufacturer focus on such things is motivated by an awareness that more people will replace tires sooner if they are so advised (and fear plays a part). It is obviously taking hold. The prevailing opinion on every auto and motorcycle message board is very much in line these days with the current conservative recommendations, and one disagrees with it at their peril (as you see here!)

 

[CapriRacer]

Welcome to my world, guys!

How does a manufacturer communicate good, reliable advise on this subject without also having good, reliable information to base it on?

We know that:

1) rubber deteriorates over time

2) the higher the temperature, the faster the deterioration

3) there is a certain amount of fatique resistance built into rubber

4) That waxes form a protective barrier on the outside of the tire

5) That exercising a tire causes anti-oxidants (AO's) and waxes to migrate to the surface of a tire.

So how do we quantify this so that a consumer has some reasonably definitive guidelines to go by?

Well, some folks look at the worst case scenario - like operating tires in Phoenix - and have concluded that they ought to say that 6 years is the limit.

Other folks have said that in a place like Minneapolis, tires can last as long as 10 years and still not be as bad as if they were used in Phoenix - but they feel uncomfortable not offering some sort of guideline - so they offer 10 years.

Still others don't feel comfortable offering a guideline.

Needless to say this is a very complex subject with no straight forward answers.

 

[dailydriver]

One way around all of this is to purchase tire models (or sizes of a specific model) that have just been released, or were only available for a few months, like I did with the BFG Super Sport All Seasons.

J/K, I know this is not always possible.

 

[George7941]

Originally Posted By: alreadygone
Originally Posted By: glennc
Russell, really, don't worry about it at all. Tires come with a preservative that is designed to make sure they don't deteriorate in storage. They will be as good in every respect as if they had been made yesterday.

There is a lot of alarmist nonsense in my opinion that is making people freak out about perfectly good new tires.


And any other aspect of automotive service when brought to discussion here! Aren't we ALL glad lubricants don't have build/best by dates on container. Imagine all the guys who'd be disposing of their "stash" every couple of years!

Bob



Ah, Bob, lubricant containers have the manufacturing(packaging) date on them. I check the dates on oil containers when I buy them (just as I do with tires) and have never had to refuse or return oil(or tires) because of age.

I bought a pair of Bridgestone DMZ3 tires a couple of months back and noticed that the tires were manufactured about fourteen months ago. I did not complain because I got a very good price on the tires. If I had paid the regular price on the tires I might have mildly complained about the fourteen month age.

 

[Russell]

Originally Posted By: Russell
Another reason for old stock being sold is my tire size (225x60x15)is being phased out as new models replace older tires. One example: Bridgestone replaced the Turanza LS-H with the Turanza with Senerity-but NOT in my size. This may help explain why Michelin has "old stock" in my size. It is a slow moving tire, so they are not making many in my size to add to their national inventory. Therefore the warehouse has only older tires??


Forgot to mention that the price I paid was about the same as Tirerack+shipping and installation.

 

[mrsilv04]

Originally Posted By: glennc
Instead I see people taking already conservative recommendations, inappropriately applying them, and then having a fit when reasonable people don't fall in line with their flawed conclusions.


I include quotes from industry experts, and you don't.... but you're the one who talks about other people and their flawed conclusions.

My first mistake was responding to anything you wrote, instead of spending more time on CapriRacer's posts...

 

[glennc]

Mrsilv I was overly harsh with that comment and I apologize for that. It was not directed at you or any other single person but more at a sort of exaggerated safety consciousness among certain segments of the public that is, I would say, non-rational in that it is not responsive to objective analysis.

I still say that nothing in this thread, including the quotes you supplied, has shown evidence that properly stored new tires lose any significant percentage of their capacity for performance or longevity over three years.

 

[Russell]

My tire dealer called me today and offered to replace the tires with another brand that would be somewhat newer. However, they said, In their opinion, the Michelin is a better tire than what is available in my size in other brands especially due to availability. My size 225x60x15 is being phased out by many manufacturers and evidently is getting harder and harder to find "fresh" tires in any Brand. At least that is what I have observed.

One example: Bridgestone replaced the Turanza LS-H with the Turanza with Senerity-but NOT in my size. This may help explain why Michelin has "old stock" in my size. It is a slow moving tire, so they are not making many in my size to add to their national inventory. Therefore the warehouse has only older tires.

Anyway, I declined to replace the tires. These tires seem to work fine.