How can you really tell how old a tire is?

[ichthos]

I have followed many discussions on tires and have heard frequent comments on how old a tire is. Is there really a way to tell how old a tire is? From what I understand the way you tell how old a tire is is to look at the last four or three digits, depending on just how old the tire is. If the tire was produced in the year 2000 or after you look at the last four digits following DOT. Of these last four, the first two tell what week they were produced, and the last two tell the year. On tires produced before this date, there are three numbers. The first two tell the week and the last digit tells the year. Tire manufacturers only showed the last digit for the year because they did not consider that a tire would be on the road after ten years. So for a tire like a Michelin Redline, how can you really tell how old it is?
Thanks,
Kevin

 

[Guest]

Ask it! :lol:

 

[Guest]

Aren't there date codes??

 

[Guest]

Dummy, guess I should'a read the whole post.


OK, ask it....

 

[Don Elliott]

A tire with the code 428 means that it was manufactured during week 42 of 1998.

If the code reads 1606, it was manufactured during week 16 of 2006. CBS or ABC had a show I saw re-broadcast on Yahoo News where this was all explained. Tires on special manager's sales both at Walmart and at Sears were found to have been manufactured 8 and 10 years ago. It is suggested that no-one should be driving on tires older than 7 to 10 years. Even if they have never been used before - don't use them. My set of Michelin 165 SR 15s lasted me 10 years with 44,000 miles and then I got ply separation.

Drivers who experience a blow-out with over-aged tires have all been buried.

 

[TheSearcherMan]

You can't. 1978, 1988, 1998, you can't tell. That's why they changed it so you could.

 

[BobbyD]

Here's what Tire Rack says on their site:

Tires Manufactured Before 2000

The Tire Identification Number for tires produced prior to 2000 was based on the assumption that tires would not be in service for ten years. While they were required to provided the same information as today’s tires, the week and year the tire was produced was contained in the last three digits. The 2 digits used to identify the week a tire was manufactured immediately preceded a single digit used to identify the year.

 

[swift6]

I think of it this way, if there are only three digits then you know it is over 8 years old. Not worth the chance of driving on.

 

[Geo Hahn]

I'd say that if it has a 3-digit code it really doesn't matter what decade it is from... it is old.

We've had multiple incidents on club drives from sudden failure of aged tires. Thankfully none resulted in injury but but one resulted in damage that would have totaled most cars. It was a big Healey so worth saving -- now in year 10 of restoration. A tough lesson to learn.

 

[DNK]

Boy -In that case anybody want to buy a set of 4 tires with only about 4 thousand miles on them?
Interesting ho they where made about a year apart?
Can't tell when the other two were made ,the # is in thew inside

And

 

[Silverghost]

Ok, maybe I missed something but I think you are looking at the wrong numbers. According to the previous posts, 9211 would mean the 92nd week of 2011 and 9220 would mean the 92nd week of 2020? What numbers are in the next area over? In the upper pic, you can see 05.. This would be the 5th week of something.... Can you post pics of these?

 

[Brooklands]

From the original reports, I thought all the numbers with date of manufacture were on the inside sidewall when the tire is mounted on the car. But I could be wrong AGAIN.

 

[DNK]

It depends on what way the tires are mounted. My cay was purchased by by me in 96. The car had had sat for a couple of years. So the tires were made in the 22 week of 90 and the 21 week of 91???
this is all conjecture though

 

[Brooklands]

If the tires are the ones that were on the car when you purchased it, that means they would be a minimum of 12 years old no matter what numbers are on the tires.

 

[DNK]

Exactly, and as it has not seen pavement except twice while I washed it the last 11 years it is a good bet.
But they look good.

 

[TR3driver]

I'm with Peter, I don't think those are the date codes.

Although DOT markings started in 1968, I don't think the date codes started until somewhat later, like late 70s or early 80s. So it's at least possible those tires don't have date codes.

Here's a link to the Tire Rack article
https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=11

Also, if that is the modern format of DOT number, here's something else I came across that might say they should be replaced:
https://www.saturnfans.com/forums/showthread.php?t=77550

 

[ichthos]

I think that Don's date codes are correct. If the tires were made before 2000, which Don acknowledged, then you would just look at the last three numbers of the DOT code. That would mean that two of the tires were made in the 21 week and the year of 1991, 1981, or 1971. The other two tires were made the 22 week in the year of 1990, 1980, or 1970. I was just curious if I was missing something because some people commented they knew the year of the tire from pre 2000 year tires which posts have confirmed is impossible. I guess the best point made is that if it is made before 2000, you shouldn't be driving on them anyway. I was just wondering if some of the pre 2000 date codes are such that they could pass for newer tires if you were to look at the last four numbers instead of the last three.

 

[BobbyD]

The Tire Rack article also states "...........there was no universal identifier that confirmed which decade (tires produced in the 1990s may have a small triangle following the Tire Identification Number to identify the decade"

So a small triangle after the code would indicate the 90's decade.

 

[NickMorgan]

My new tyres just arrived today and I see the date code is 1908. Either they are one hundred years old or they were produced in April/May this year!

 

[Don Elliott]

I'm glad you looked. You will have 10 years of knowing that your tyres are safe. Let us know what your impression of them is after you try them for a week or more on "DRY" (not muddy) roads.