Why a new tire is not always a new tire.
Tire rubber breaks down over time as the rubber dries out and hardens and becomes less elastic or flexible. Sometime after six to ten years the tire can be unsafe to use, especially at higher speeds, higher loads or in hot weather.
If you have an older car that hasnâ€™t been driven much in the last 6-7 years, going for a long drive at higher speeds could result in tire failure or even a blowout which often causes injuries or worse.
But you bought those tires just a few years ago so you are safe, right?
Not necessarily so.
You can buy brand new perfectly good looking tires that are 4 - 10 years old but still on the shelf. This is especially true when buying or online or discounted tires or sizes that don't turn over very fast. Buying used tires can be very risky also. So how do you tell?
Hidden in the cryptic Tire Identification Code (serial number) on the side of a tire (sometimes on the inside of the tire where it is hard to see) is a date code that identifies which week and year the tire was produced.
In the 1990's it is the last 3 digits, but starting in 2000 they used 4 digits. The first two indicate how many weeks into the year. The next number or numbers indicate the year.
XXXXXXXX 0608 Manufactured during the 06th week of the year 2008.
XXXXXXXX 0600 Manufactured during the 06th week of the year 2000.
Examples of Tire Date Codes.
49th week of 2007
8th week of 2001
33rd week of 1994
This last tire was found on a vehicle at Wayne's Garage in January of 2010. It was installed on the front, the other side of the tire had cracking near the rim.
NHTSA has been asked to require tire manufacturers to put expiration dates on all new tires.
In Europe, vehicle manufacturers typically recommend replacing tires that are more than six years old.
The investigative TV show 20/20 has in the past reported on investigations of places selling 6 - 8 year old tires that are still on their shelves.