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Industry watcher Sean Kane, who investigates auto safety issues for attorneys, uncovered at least 20 cases in which old tires, some barely used, have disintegrated causing accidents. The cases led to 10 deaths.
"We suspected for some time that the industry has been unwilling to tell the public how serious a problem it is," said Kane, a partner with Arlington, Va.-based Strategic Safety. "Tires as a commodity should have a shelf life or expiration date on them."
Kane isn't the only one concerned about this issue. Last week a British trade association, the Tyre Industry Council, issued the tire industry's first ever warning on the subject, imploring people to refrain from selling tires six years old or older and to not use any tires 10 years old or older.
In addition three major German auto manufacturers, Mercedes-Benz, BMW and Volkswagen, include warnings about using older tires in their owner's manuals. There is also a concern about spare tires, because they sit so long until needed.
Tires Degrade Over Time [my emphasis]
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I can't stress this enough and I don't know how many times I've had this conversation with customers. They look at me sideways when I tell them they should replace tires that don't look bald or worn funny. Sunlight and heat have a deteriorating effect on your tires. So does feeling the curb with the right side rubber as you park. What's even worse is a car that sits for months at a time. Hitting potholes also distorts the steel belts under the tread. 45,000 - 60,000 miles should be the rule of thumb in normal driving conditions (10,000 - 15,000 miles/year), 4 - 6 years if you're like the little old ladies from the neighborhood who just go to church and the IGA. Might be a good idea to get a wheel alignment when you put those new sneakers on too. Your new rubber won't wear out as fast and the car will handle better.