How can you compare tires between makers or between tire lines? A good place to start is the Uniform Tire Quality Grading (UTQG) system. Developed by the U.S. Department of Transportation, UTQG requires manufacturers to grade their tires in three important areas: tread wear, traction and temperature. The UTQG grade for each tire is molded right on the tire and is also on the paper label attached to a new tire.
Tread wear Grade A tire with a tread wear grade of 400 should have a useful tread life approximately twice as long as a tire with a tread wear grade of 200. The higher the grade, the better the expected tread wear. But keep in mind that makers test their own tires against an original standard. Some manufacturers are more ... optimistic ... than others. So this grade is best used to measure tread wear within a single maker's line, not between makers.
Why a grade instead of a mileage rating? The wear grade is not given in miles because the test is very short compared to the life of the average tire. Also, actual mileage depends on the type of car or truck, the type of roads it covers, weather and driving style. Most tires come with a "mileage warranty" that tells you how many miles the maker expects that tire to go.
Traction Grade is based on the tire's ability to stop on wet pavement, again as measured under controlled conditions on wet asphalt and concrete surfaces. The grades, from highest to lowest, are designated AA, A, B, C. A tire that is graded AA should stop better on wet surfaces than a tire with a lower grade.
Temperature Grade is based on the tire's resistance to heat and its ability to dissipate heat. The grades, from highest to lowest, are designated A, B, C. An A-rated tire is the coolest running, while a C-rating meets the minimum federal performance standards. These grades are set based on a tire that has the right amount of air and carries a normal load.
The UTQG ratings are a good way to start comparing tires. But of course you need to think about price, warranty, looks and reviews, too. The more you know, the better you can do for your car or truck.