DOT (Department of Transportation) Uniform Tire Quality Grades apply to passenger vehicle tires and supplement federal safety requirements established for tire performance and construction.
Where applicable, quality grades are molded into the tire sidewall between the tread shoulder and the maximum section width. A typical example may appear as follows:
Treadwear 200 Traction AA Temperature A
Treadwear
The treadwear grade provides a comparative indication of tire wear performance based on testing conducted under controlled conditions on a designated government test course.
For example, a tire with a treadwear rating of 150 is expected to wear one and one-half times as long as a tire rated 100 when tested under identical conditions on the government course.
Actual tire life on your Nissan Kicks may vary considerably from these ratings. Factors such as driving style, road surface conditions, vehicle loading, maintenance practices, climate, and tire inflation pressures can all influence tire wear performance.
Traction AA, A, B and C
Traction grades are assigned in descending order as AA, A, B, and C. These ratings indicate a tire's ability to stop on wet pavement during controlled straight-line braking tests performed on specified asphalt and concrete test surfaces.
A tire receiving a grade of AA offers the highest measured wet braking traction, while a tire graded C represents the lowest performance level permitted under the grading system.
WARNING
The traction grade assigned to a tire is based solely on straight-line braking traction tests. It does not evaluate acceleration capability, cornering performance, hydroplaning resistance, or maximum available traction under all driving conditions.
Temperature A, B and C
Temperature grades are identified as A, B, and C, with Grade A representing the highest level of heat resistance and heat dissipation capability.
These ratings are determined through laboratory testing performed under controlled conditions on a specified indoor test wheel. The grade reflects the tire's ability to withstand heat generated during operation and to dissipate that heat effectively.
Excessive heat is one of the primary factors affecting tire durability. Prolonged exposure to high operating temperatures can accelerate tire deterioration, reduce service life, and increase the likelihood of sudden tire failure.
Grade C represents the minimum level of performance required for passenger vehicle tires under Federal Motor Vehicle Safety Standard No. 109. Grades B and A indicate progressively higher performance levels than those required by federal regulations.
WARNING
The temperature grade for a tire is established under conditions where the tire is properly inflated and not overloaded. Excessive speed, insufficient tire pressure, vehicle overloading, or any combination of these factors can generate excessive heat buildup and may result in tire failure.