Did You Know… Tires Have An Expiration Date?

With gas prices these days, you often hear about keeping your tires properly inflated. You might also rotate, balance, and check your tires regularly for wear, but most drivers do not know that their tires have an expiration date? Tire defects aside, just because a tire looks brand new does not mean it is safe to use. Modern tires are highly engineered products that must withstand the weight of a car plus the forces from braking and turning while providing a comfortable ride and increased gas mileage. Even without exposure to heat and friction from the road, certain tire compounds like natural and synthetic rubbers decompose over time.

Automotive experts and safety advocates call aged tires a "hidden danger":

http://www.youtube.com/watch?v=u9wvRrqSP1k

The dangers of aged tires were also featured on 20/20:

http://www.youtube.com/watch?v=mDgSk5xWkrI

Tire manufacturers must provide the date on which the tire was manufactured, but not the date by after which the tire should not be used. To make matters worse, the "born-on" date is provided using a cryptic code that most consumers – and even many tire installers – are unable to accurately read and, until only recently, were placed on the inside wall of the tire making it very difficult to even find.

How do you know if your tires are too old? Experts have warned that tires more than six years old can fail catastrophically. In other words, the brand new tires that you just installed could blow out and lead to severe injury or death if they are simply too old. In spite of mounting pressure, tire manufacturers have been reluctant to issue expiration dates. It is possible that tires may wear out well before the expiration date with wear and exposure to a host of other factors that affect the useful life of a tire. For instance, exposure to heat, sunlight, ozone, etc. will all shorten the lifespan of a tire, even if there is plenty of tread remaining. Spare tires are particularly at risk, because they can sit in the trunk of a car for years without replacement. However, if your tires are in otherwise good condition, consumer safety analysts recommend changing your tires before they reach six years of age.

So now that you know that tires need to be replaced after 6 years, how can you find out how old your tires actually are? Although tire manufacturers are required to stamp the date of manufacture for each tire, it might not be immediately obvious where to locate such information on the tire sidewall. In order to determine the age of your tires, TireRack.com has posted the following guidelines:

Each tire has a required Department of Transportation (DOT) number imprinted on at least one of its sidewalls. That number begins with the letters "DOT" and may contain up to 12 additional numbers and letters. The first and last digits are the most important.

• The first two letters or numbers identify the manufacturer of the tires.
• Prior to the year 2000, the last 3 digits of a DOT number represented the week (2 digits) and the year (1 digit) of production. So if the last three digits are 408, the tire was produced in the 40th week of the 8th year of the decade. There was no universal identifier that confirmed which decade in which the tire was manufactured (however, tires produced in the 1990s may have a small triangle following the Tire Identification Number).
• Tires produced after January 1, 2000, have a 4-digit date code at the end of the DOT number. The first 2 digits represent the week of production and the last 2 digits represent the last 2 digits of the year of production. So, 5107 indicates the tire was produced in the 51st week of the year 2007.

Tires are the only part of your car connecting you to the road. Even the most expensive sports cars cannot outmaneuver a tire blowout. Make sure you take adequate precautions to keep you and your loved ones safe by checking the condition of your tires regularly and replacing them before they are too old.