tire sidewall code

Exclusive summary about Tire Code by Gregg Hall

One sure shot way of knowing exactly the type of tire your vehicle would need is by deciphering the tire sidewall code. First up are the markings on tire size. The aspect ratio is the ratio of tire width to sidewall height.

First up are the markings on tire size. (Example: P195/60R15 87Q)

• P stands for Passenger. You may find other abbreviations in place of P, for example:
• LT for Light Truck and T for Temporary/Spare tire.
• 195 stands for the width of the tire in millimeters between the sidewalls.
• 60 stands for the aspect ratio. The aspect ratio is the ratio of tire width to sidewall height.

• R indicates that the tire has a radial construction. You may find other abbreviations in place of R, for example, B which indicates Belted Bias or D that represents Diagonal Bias.

• 15 next to R indicate the rim or the wheel diameter in inches.

• 87 represents load index.

• Finally Q (or at times H, S, T, U, V, W, Y, etc.) represents the speed rating. Under ideal situations, the top speed attainable by the tire is indicated by the speed rating.

UTQG Ratings

The general treadwear grade is standardized at 100. So if you see 200 as treadwear rating then it indicates that the tire will wear twice as well as a tire with a 100 treadwear.

Traction grades are generally indicated by letters: AA to C. AA is the highest grade while C indicates that on wet asphalt and concrete, the braking power of the tire is poor.

The tire's resistance to heat and dispel heat is indicated by Temperature grades. Temperature grades are also indicated by alphabets. A indicates that the tire can resist heat well, B indicates that it cannot resist heat as good as a tire with A rating and C barely passes the minimum standards for safety.

Tire Codes - Understanding What the Numbers on Your Tire Mean

Exclusive summary about Tire Code by Dirk Gibson

Every tire has a unique purpose. To understand what you have and the type of tire you need, you have to grasp what the tire code on the side of the tire means.

It refers to the type of car the tire is intended for. "P" always refers to a tire intended for a passenger car. "LT" refers to tires intended for trucks.

The first number in code refers to the tire width. It refers to the type of tire design. R refers to a radial tire. Radial tires go on passenger cars. LT refers to truck tires.

The final letter and number combination refer to the specs on the tire.