TireTalk

When looking for tires on the internet, you may come across the abbreviation UTQG. What does UTQG (Uniform Tire Quality Grade) represent, and what do you need to understand about UTQG ratings?

WHAT DOES A UTQG TIRE RATING ENTAIL?

The UTQG rating system was developed to assist drivers in making better tire purchases. The following are the grades that tire manufacturers assign to their own tires:

• Traction
• Treadwear
• Temperature

These values add up to a tire’s UTQG rating, which is a three-digit number followed by two letters, such as 300 AA.

You may also check the UTQG rating of your existing tires by looking at the sidewall beneath the tire size.

These figures are calculated by comparing the functionality of a tire to the performance of a conventional control tire.

What does both of the UTQG actually tell you regarding your tire’s quality? Here’s how it works.

WHAT CAN YOU LEARN FROM UTQG TIRE RATINGS?

TREADWEAR GRADES

The treadwear rating is intended to give you an idea of the tire’s resilience or life expectancy. The most important thing to remember about the treadwear grade is that the higher the number, the longer it will take for the tread to wear down. The higher the number, the better.

Treadwear grades from the UTQG are based on real road use, with the test tire being driven in convoy beside standardized Course Monitoring Tires. For a total of 7,200 kilometers, the vehicle runs a predefined 400-mile test loop in West Texas. Every 800 miles, the vehicle’s alignment, air pressure, and tires can be checked and rotated. The wear of the test tire and the Monitoring Tire is measured both during and after the test.

The tire manufacturers then assign the Treadwear Grade based on observational wear rates. A grade is provided to the Course Monitoring Tire, and a grade is given to the testing tire reflecting its relative treadwear. A grade of 100 indicates that the tire tread will survive the same amount of time as the test tire, a rating of 200 indicates that the tread will last times as large, a grade of 300 indicates three times as long, and so on.

A treadwear grade of 100 is assigned to the control tire. If a tire receives a treadwear rating of 200, it is projected to wear out twice as quickly as the control tire. Tires run a 640-kilometer course for 11,520 kilometers to get a treadwear rating, with tread thicknesses evaluated every 1,280 kilometers to determine an estimated tread life.

UTQG Treadwear Ratings are subject to interpretation by the tire maker because they are awarded after the tire has only received minor treadwear over its 7,200-mile journey. This indicates that tire manufacturers must interpret their raw wear information when awarding Treadwear Ratings, and their test scores can reflect how cautious or enthusiastic their marketing team is to some level. Comparing the Treadwear Levels of various tire lines within a specific brand is usually helpful; however, comparing the ratings between other brands is not.

TRACTION GRADES

The UTQG Traction Ratings are determined by the tire’s moist coefficient of adhesion in a single direction as it skids across the prescribed test surfaces. Smooth braking, dry turning, wet cornering, and high-speed hydroplaning resistance are not assessed in the UTQG traction test.

Mounting properly inflated test rubber on the engineered axle of a “skid trailer” determines the Traction Grade. The skid trailer is dragged behind a truck at a steady 40 mph on wet pavement and wet concrete test conditions. Its brakes are temporarily locked, and axle detectors track the tire’s friction coefficient (braking g forces) as it rolls. Because this test assesses a slipping tire at a constant speed of 40 mph, it focuses more on the tread composition and less on the tread pattern.

The traction grade of a tire indicates how well it can brake in rainy conditions. The greatest traction grade is AA, with A, B, and C following closely behind. Tires including an AA traction grade should brake in much less time than those with a C traction grade.

TEMPERATURE GRADES

The UTQG Temperature rating is a measurement of how much heat a tire generates and dissipates. The tire’s capacity to drive at high speeds is limited if it cannot adequately dissipate heat or withstand the damaging effects of heat buildup. The grade is determined by driving an inflated test tire against a large diameter high-speed laboratory test wheel to determine a loaded tire’s ability to perform at high speeds without failure.

Tires are constantly exposed to the heat stress that might occur when traveling at high speeds and in hot conditions. Blowouts can happen when a tire becomes too heated.

The temperature rating indicates how effectively a tire can withstand heat build-up. The heat resistance is rated as A, B, or C, with A being the best and C being the worst.

While knowing the UTQG might help you make better judgments when evaluating summer, all-season, winter, and all-weather tires, keep in mind that the ratings are offered by makers and can be biased.

HOW DOES THE UTQG OPERATE?

Treadwear, for example, is a numerical indication of how well a tire degrades compared to a reference tire instead of a mileage forecast. A tire with a “200” rating, for example, will last twice as long as one with a “100” rating. That’s helpful, but it doesn’t indicate how long the tire will endure. For most buyers, the manufacturer’s tread-wear guarantee in miles is not only more apparent, but it also serves as an excellent barometer because the manufacturer is responsible for paying if the tire fails to meet the warranty’s expectations.

On wet pavement, the traction grade assesses the degree of grip. The best grade, AA, is earned by the majority of ultra-high-performance tires. Only one tire (out of over 2,400 models) receives a C grade, whereas most car tires receive an A. Less than 22% of tires receive a B. Although not much of a recommendation, we strongly advise purchasing a tire with a traction rating of at least an A.

The temperature grade, which was developed during the radial tire development, is a measurement of how effectively a tire resists heat buildup. More than a third of the tires receive an A rating, with 59 percent receiving a B rating and roughly 11 percent receiving a C rating. Look for a tire with a B or higher rating.