Tire Treadwear Ratings Explained

tire tread wear rating explained z one automotive

Tires that wear out too quickly put you at risk. Examining the tread wear on a tire is critical to helping you determine how well your car will survive in extreme driving conditions such as wet roads. Until recently, the only reliable information to help you determine treadwear was the claims from manufacturers and treadwear ratings from the government.  Today, you can access Uniform Tire Quality Grading (UTGQ) ratings to help you determine your tires’ tread wear, traction and its resistance to temperature. Often, you will come across complex UTGQ ratings, which make it hard for you to understand the available information and make a decision if you are not aware what different numbers and letters mean.

The existing UTGQ ratings available to help you assess treadwear include:

Treadwear

Treadwear grades as seen on the side of the tire indicate the time a tire will take to wear down; a high number shows that the tire is likely to last long. Treadwear tests take place in controlled environments. In the testing process, manufacturers fit four vehicles with the test tires and then run them in convoy concurrently. Each vehicle runs repeatedly for 64kms on a specific course for up to 11,520kms. The tire testing team measures tread depths after every 1,280kms and then calculate an average of all the figures to come up with a projected wear time. The test process also involves a test on ‘standard’ control tires, which serve as a comparison for all the test tires. For example, in case the control tire is of grade 100, the test tires of grade 200 should take twice as long as the control tires to wear down. Often, treadwear tests happen under the supervision of manufacturers making it hard to compare between two similar tires by different manufacturers. Additionally, manufacturers control the quality of the tests, as there are no standardized tests to give you the comparative data you need to choose the right tire.

Temperature

Temperature grades available on the tires help you determine the tires’ resistance to heat, with higher grading indicating a higher resistance to heat generation especially when the car is at speed. A tire with low heat resistance can easily break down when you are driving fast or for long periods especially in hot weather. Heat resistance grading begins with an A rating as the highest, where your tire can cover a long distance at 155 miles per hour, and C rating, where your car can run between 85 and 100 miles per hour safely, as the lowest. However, all UTGQ rated tires must be able to operate safely at least 85 miles per hour. While the temperature rating can help you when choosing the best tire for extremely hot driving conditions, it does not give you sufficient information on the effects heat resistance has on treadwear and overall durability of your tires.

Traction

The traction grading on your tires helps you assess their ability to stop fast on wet surfaces. Traction grading begins with AA as the highest rating, then BB and CC as the lowest rating. While tire traction may help you understand your tires in wet conditions, you will need to speak to an auto expert to understand their behaviors in dry braking and their hydroplaning resistance.

UTGQ ratings help you understand your tires better, and give you a simple starting point when making a decision. While they simplify your understanding of tires, there is so much more to tires than treadwear you need to consider when choosing a new fit for your car. For further information on understanding your tire’s treadwear, please contact us at Z-One. We can be found online at Z-OneToledo.com or reached directly at 419.478.3402.