July 23,2008

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The Uniform Tire Quality Grading System (UTQGS) is a tire information system designed to help buyers make relative comparisons among tires. The UTQGS is not a safety rating and not a guarantee that a tire will last for a prescribed number of miles or perform in a certain way.

It simply gives tire buyers additional information to combine with other considerations, such as price, brand loyalty and dealer recommendations. Under UTQGS, tires are graded by the manufacturers in three area: treadwear, traction and temperature resistance.

The UTQGS information is right where you need it . . . on the tires. The grades can be found on two places on the tire:

There is a paper label affixed to the tread, and the grades are also molded into the sidewalls. Additionally, brochures which explain the tire grades are available at tire stores.

Treadwear

The treadwear grade is a comparative rating based on the wear rate of the tire when tested under carefully controlled conditions. For example, a tire graded 200 should have its useful tread last twice as long as a tire graded 100.

However, real world tire tread life, in miles, depends on the actual conditions of their use. Tire life is affected by variations in driving habits, service practices . . . such as tire rotation, wheel alignment and maintaining proper inflation pressure...and differences in road characteristics and climate.

Traction

Traction grades represent the tire's ability to stop on wet pavement as measured under controlled conditions on asphalt and concrete test surfaces. The traction grades from highest to lowest, are "AA," "A," "B" and "C". A tire graded "AA" may have relatively better traction performance than a tire graded "A," "B" or "C," based on straight ahead braking tests. The grades do not reflect the cornering or turning traction performance of the tires.

Temperature Resistance

Temperature grades represent the tire's resistance to heat and its ability to dissipate heat when tested under controlled laboratory test conditions. Sustained high temperature can cause the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure.

The temperature grades from highest to lowest are "A," "B" and "C." The grade "C" corresponds to the minimum performance required by federal safety standard. Grades "B" and "A" represent higher levels of performance than the minimum required by law. The temperature grade is for a tire that is inflated properly and not overloaded. Excessive speed, under-inflation or excessive loading, either separately on in combination, can cause heat build-up and possible tire failure.