by Mary Clark

Created on: January 23, 2009

Ladies, buying tires does not have to remain a Greek mystery known only to men. You too can unlock that mythical code and arm yourself with enough knowledge about tires to leave a set of perfectly laid rubber tracks in the parking lot of your local tire store.

The most important number on the tires you purchase is also the least known number in the ever-elusive equation. This rarely talked about number is not easily visible either once the tire is on your car so make sure you check it before you buy those tires. Your sales rep does not want you to know about this number, and if asked about it, he will have a set of well-rehearsed lines to offer you with the hope that you will let it slide. Do not let it slide. Your life rides on the safety, or lack of safety, contained within that number.

The number I am referring to is the manufacturing date of the tire. This number is located on the inside wall of the tire and is coded. A tire with the DOT number ending with 4804 is actually a tire made during the forty-eighth week of the year 2004. This tire while new to you may already be out of the manufacturer's warranty period. Most tire companies will honor a warranty for up to five years after the manufactured date, not from the date on which you purchased it.

The reason this is so important is that when rubber ages, it becomes brittle. A tire that appears new can be more than ten years old, which may cause uncontrollable blowouts and catastrophic accidents. New regulations shall require tire manufacturers to make this date easier to read and for that date to be visible even when the tire is mounted on the vehicle. However, this regulatory measure does not go into effect until September 2009.

Review the video: Aged Tires, a Driving Hazard, an ABC undercover report that shows leading retail outlets selling fourteen-year-old tires as "new." You will hear reports about tragic accidents directly related to the purchase of what consumers thought were new tires, but in reality were aged tires.

The remaining numbers on your tire are easy to decipher once you know how to break the number down. They deal with the measurements for your particular vehicle. For example, we will say that your car requires a tire with the number P 235-60R-16. The letter P designates that this tire is for a passenger vehicle. The 235 states the tire's width, in millimeters. The number 60 reflects that the height of the tire is sixty percent of its width. The letter R identifies that your tire is a radial. The number 16 refers to the size of the rim that this tire will fit. However, understanding these numbers without taking into consideration the date the company manufactured the tire will not give you a safe ride.

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