SEMA eNews, Vol. 10, No. 2 – January 10, 2007
Officials at the National Highway Traffic Safety Administration (NHTSA) believe that they have developed a test for determining the durability of aged tires. It reportedly involves subjecting a tire to high temperatures (up to 150 degrees Fahrenheit) for 8-to-10 weeks in a high oxygen environment. The test was given a stamp of approval by “The Aged Tire Durability Task Group,” a 33-member task force which includes representatives for tire makers, the auto industry and safety groups. The Task Group was formed in 2002 to establish a tire durability test. The Task Group also endorsed its own, separate durability test that would run tires at about 75 miles an hour for more than 30 hours.
NHTSA is required to report its tire durability test findings and recommendations to Congress by August 2007. At issue is the claim that some rubber compounds degrade over time, even if unused. NHTSA has been in the process of studying the topic but has found that it may be difficult to establish a uniform time limit that does not take into account other contributing aging factors such as climate, handling and storage. Several auto companies are backing a 6-year tire expiration date and a number of safety advocate groups are urging NHTSA to institute a regulation.
While supporting tire expiration research, SEMA believes it is important that regulators and lawmakers have the best science available before making any decisions on this topic. They should also consider the associated environmental, social and economic costs if expiration dates lead to premature tire scrappage. If a regulation were proposed, SEMA would likely seek a provision that exempts limited production tires (15,000 or less annually) and other specialized tires, similar to that already included in a California law requiring replacement tires be as fuel efficient as OE tires. (The law has yet to be implemented.) Meanwhile, SEMA urges consumers to also focus on critical safety issues such as tire inflation and overloading of vehicles.
In a separate but related rulemaking issued several years ago, as of September 2009 tire manufacturers will be required to print the tire’s manufacture date in an easy-to-read, four-digit code on the outside of tires. The date is currently printed on one side of the tire but coded in a fashion that it is difficult to decipher by most consumers and frequently facing inside when the tire is mounted. For more information, contact Stuart Gosswein at firstname.lastname@example.org