Cars 101: Reading The Tires.

Photo courtesty of joeandjamie.com

Everyone who’s had a car has surely either dealt with a flat tire, or knows someone who has.  Or, you’re someone who changes their tires during the year between summer and winter tires to maximize the car’s capabilities over the year.  Inevitably, you get stuck ordering a new tire at some point, for one reason or another.  Those markings on the tire’s sidewall can be extremely confusing for first-timers, so here’s the easiest way to decipher them:

The first character is usually a letter, most likely “P”, which stands for passenger car.  The next set of three numbers specifies, in millimeters, the tire width from the inside to the outside tread.  The two numbers that follow the slash specify the sidewall width, or the profile, of the tire.  The next set of two letters are the tire’s speed rating and type.  In general, the further along the letter is in the alphabet, the higher the tire’s top speed rating is.  The final two numbers determine the inner width of the tire, in inches.  Note as well that “M+S” usually stands for “Mud and Snow” and will normally denote a winter or all-season tire.

-Al