Because the safety of your family and friends is riding on them.
Do you know how old your tires are? Why should you care? Because your safety and the safety of your family, and your friends are riding on them.
The federal government, through the Federal Motor Vehicle Safety Standards, requires tire manufacturers to label tires in a very specific manner with a variety of information.(1) The Standards not only require some obvious choices, such as the size of the tire, the maximum inflation pressure, the name of the manufacturer, as well as the brand name or number, but they also require a Tire Identification Number (TIN) be included on the sidewall of your tire. The typical TIN looks something like this, “DOT MA L9 ABC 0307.” Unfortunately, there is currently no requirement that the manufacturer, distributor, or retailer must bring the code to the consumer’s attention, much less decipher it. So let’s break it down. By imprinting “DOT” on the tire, the manufacturer is certifying that its tire meets or exceeds the Department of Transportation’s Safety Standards; “MA” is a code number assigned by the DOT to a particular manufacturing plant; “L9” represents the tire size; “ABC” is a group of symbols that the manufacturer can use to identify the brand or other significant characteristics of the tire; and “0307” indicates when the tire was manufactured. “0307”??? Unless you’ve handled a tire failure case, these four numbers probably still don’t mean much. A tire imprinted with “0307” in the last four spots of the TIN was manufactured the third week of 2007.
The full article can be read here.
(1) The National Highway Traffic Safety Administration has a legislative mandate under Title 49 of the United States Code, Chapter 301, Motor Vehicle Safety, to issue Federal Motor Vehicle Safety Standards (FMVSS) and Regulations to which manufacturers of motor vehicle and equipment items must conform and certify compliance.