Age of Tires

[naparsei]

I know about decoding the DOT part of the tire code, but when did tires switch from using 1 digit for the year to 2 digits?

Most new tires I have seen say "02" or "03" for the tire year of manufacture, rather than just "2" or "3".

[RickM]

Perhaps this applies....

"D.O.T. Serial Number: Shows compliance with Department of Transportation regulations along with the coded name of the tire manufacturer and the place and date of manufacture. The date of manufacture is shown by the last three digits of the serial number -- if it ends in 405, that means the tire was made in the fortieth week of 1995. Because rubber can dry out and deteriorate, tires that are extremely old can be more prone to failure than newer tires."

There's also a push to provide a "Use by" date on tires as it's been found that tires that are 6 years or older can be unsafe.


EDIT: "Prior to year 2000 three numbers are used for the Date of manufacture, first two numbers identify the week and the last number identifies the year of manufacture. To identify tires manufactured in the 90's a decade symbol (a triangle on its side) is located at the end of the DOT serial number."

There are exemptions from providing a date, one being for tires that come on a new car and for vehicles over 10,001 lbs.

[naparsei]

Rick,
I understand. Thanks for the response. However, for example, my Honda Pilot's tires say 4703, meaning late 2004 manufacture. If my tires say, for example, "172" does that mean week #17 in 2002 or week #17 in 1992. Obviously, there is a huge difference...

[Jeff]

I think it changed in 2000 to a two digit year code.

[RickM]

Yes, what Jeff says makes sense.

Learn something every day.

[Jeff]

4703 means 47th week of 2003.