Automakers such as Ford Motor Co. and DaimlerChrysler have publicly advised that tires be replaced after six years. And, last November, Bridgestone/Firestone North American Tire (BFNAT) recommended a maximum life span of 10 years for passenger tires.
However, the Rubber Manufacturers Association (RMA) says there is no concrete evidence available to support an expiration date for tires. NHTSA plans to begin testing procedures within the next few years, according to reports.