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Tread Wear Ratings

The Tread wear Grade of a track tire is the numeric portion of the Uniform Tire Quality Grade Standards (UTQG) that are printed on the sidewall of a track tire. These tread wear standards were enacted by the National Highway Traffic Safety Administration (NHTSA), which is part of the United States Department of Transportation (DOT). Higher tread wear numbers indicate that the tread of a track tire, and hence the track tire itself, should last longer.  Tread wear ratings are only found on DOT approved tires.

The Tread wear Grade describes how a track tire manufacturer views the wear of a given track tire. In theory, this means that a tire with a 80 grade will wear twice as long as a tire with a 40 grade. However, tire manufacturers are not obligated to grade a tire based on the test results or compare them to other manufacturer tires, except to say that they can not overstate the grade. This is enforced by NHTSA requiring documentation to justify any assignment of a grade on a tire.

Notice that the tread wear grade is a ratio and not a mileage. This is because there are a lot of factors that determine tread wear rates and most of them are a function of driving conditions and operating environment, and not the track tire itself. As a result, actual track tire wear will vary considerably within the same track tire line. The phrase "Your mileage may vary" applies here. In staying that, 2 track tires with the exact same compound, should have a tread wear rating that varies in accordance with tread depth.

Solely the track tire manufacturer does the assigning of UTQG grades. In many cases, this has resulted in the UTQG grading system to be more of a marketing tool than was originally intended.