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Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 05:35
by Oldiebut goodie
Since 2000 according to Dunlop (South Africa) - but doesn't say whether that is a compulsory enactment. I am sure the UK is before that. Kev will have the info. at his fingertips.
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Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 05:45
by Nicola&Tony
Thanks, I've just been googling and found some more info about dot codes here:

http://en.wikipedia.org/wiki/Tire" onclick="window.open(this.href);return false;

"In the United States, the DOT Code is an alphanumeric character sequence molded into the sidewall of the tire for purposes of tire identification. The DOT Code is mandated by the US Department of Transportation. The DOT Code begins with the letters "DOT" followed by a plant code (two numbers or letters) that identifies where it was manufactured. The last four numbers represent the week and year the tire was built. A three-digit code was used for tires manufactured before the year 2000. For example, 178 means it was manufactured in the 17th week of 8th year of the decade. In this case it means 1988. For tires manufactured in the 1990s, the same code holds true, but there is a little triangle (Δ) after the DOT code. Thus, a tire manufactured in the 17th week of 1998 would have the code 178Δ. After 2000, the code was switched to a 4-digit code. Same rules apply, so for example, 3003 means the tire was manufactured in the 30th week of 2003."


Tony

Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 05:55
by CycloneMike
Tyres were dated pre 2000

"For tyres manufactured after the year 1999, the last four numbers identify the date of manufacture of the tyre to the nearest week. The first two of these four numbers identify the week of manufacture (which range from "01" to "52"). The last two numbers identify the year of manufacture
(e.g., a tyre with the information "DOT XXXXXX2703" was manufactured in the 27th week of 2003).For tyres manufactured prior to the year 2000, three
numbers instead of four indicate the date of manufacture. Also, during the early 1990's, a triangle was added ( ) to the end of the character string to distinguish a tyre built in the 1990's from previous decades (e.g., a tyre with the information "DOT XXXXXX274 was manufactured in the 27th week of 1994)."

http://www.tyresafe.org/data/files/Tyre ... r%2008.pdf" onclick="window.open(this.href);return false;

You might find you have to look on both sides of the tyre to find the date moulding, depends on the tyre manufacturer. The bit of the tyre mould that forms the last part of the dot code date is removable, some manufactuers only date one side although the first part of the dot code may be on both sides.

Mike.

Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 05:57
by CycloneMike
Tony, you beat me to it!

Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 06:32
by Nicola&Tony
CycloneMike wrote:You might find you have to look on both sides of the tyre to find the date moulding, depends on the tyre manufacturer. The bit of the tyre mould that forms the last part of the dot code date is removable, some manufactuers only date one side although the first part of the dot code may be on both sides.

Ah, thanks for that, when it stops raining I'll get under the van and have another look.

Cheers

Tony

Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 15:37
by cumbriankeith
Just found a bit more on wikipedia under tire:
Dangers of aged tires
Research and tests show that as tires age, they begin to dry out and become potentially dangerous, even if unused. Aged tires may appear to have similar properties to newly manufactured tires; however once the vehicle is traveling at high speeds (i.e. on a freeway) the tread could peel off, leading to severe loss of control.

Many automakers recommend a six year limit on tires and several tire manufacturers (Bridgestone, Michelin) have called for tires to be removed from service 10 years after the date of manufacture. However, an investigative report by Brian Ross on ABC's 20/20 news magazine found that many major retailers such as Goodyear, Wal-Mart, and Sears were selling tires that had been produced six or more years ago. Currently, no law for aged tires exists in the United States

Re: Tyres - how old is too old??

Posted: 05 Jun 2009, 16:46
by kevtherev
the colonies tend to be far more twitchy about tyre safety than us, due mostly to there culture of litigation.

tyre technology has moved on since the all conquering G800.

the Chemistry involved in the compounds that make up various parts of the tyre is 100% more precise than 20 years ago. So I am more than happy to fit a tyre that's 6 years old, because the tests have been done and the limits are safe.
But doubt that I will ever have that opportunity, due to the computerised inventories that most tyre manufacturers employ.
Goodyear for instance operate a 12 month inventory on all codes. So I can say with confidence that the pirellis, michelin, Bridgstone, goodyear or any european manufacturer will be doing this (ISO 9002)
In other words they only make enough to satisfy demand.

As for the chinky cheapos I wouldn't know

Re: Tyres - how old is too old??

Posted: 25 Jun 2009, 20:14
by Nicola&Tony
I eventually got under the van and sure enough found the "missing" tyre codes on the inner walls of the tyres, very handy that! :roll: Three tyres were ok but the two rear ones were made in 2001 and had what looked like lots of very fine cracks on the tyre walls. With a two week trip round Wales rapidly approaching, I'm not gonna take any chances, so the tyres have been replaced. Code on the new ones is 5008. :D

Thanks for the thread fellas! :ok

Tony