Automobile tires, like many other items, do not stay new forever. When bought soon after being manufactured and installed on a car or truck, very few problems can be expected with proper inflation and regular rotation. In recent years, however more attention has been placed on just how long tires should be considered “good” and the general consensus from some government officials is that a tire should be put into service before reaching the age of 6 years old and all tires should be replaced by the 10-year mark, regardless of whether they are on a vehicle or not. 

As a tire ages, environmental factors can significantly breakdown the rubber compound of a tire and accelerate the aging process. Other significant circumstances--such as how a tire is stored—can also increase the likelihood of a catastrophic tire failure unexpectedly later on while on the highway or interstate.

Currently, expiration date do not exist on passenger vehicle tires and, with that in mind, consumers should be vigilant in choosing tires that have been manufactured recently and not stored for several years in a warehouse.  Despite the lack of an expiration date, the U.S. Department of Transportation does require that tire manufacturers place unique Tire Identification Numbers on every tire produced.  While some portions of the DOT number will be irrelevant to most consumers, the last four digits are important in determining the age of your tires.

Consumers can easily look on the sidewall of the tires and look for a series of letters and numbers beginning with “DOT”.  If the tires were manufactured after the 2000 model year for the specific tire, the last four digits will be of the most concern. If the last four digits read, “1204” it can be ascertained that the tire was manufactured in the 12th week during 2004 model year.   If the tires were produced prior to 2000, look for a three-digit code.  For example, if the code reads “529”, than the tire was produced in the 52^nd week of 1999.

When purchasing new tires, verify the date of manufacture prior to having them installed and make sure that no visible flaws are present in the treads or sidewalls. Furthermore, those purchasing tires should not assume that the date on one tire is the same as the others. Tires are often stored in warehouses for varying periods of time and are not necessarily sold together in order of production.  It is not uncommon for a vehicle to have one or two tires that are significantly older than the others.