What UTQG Grades Mean

Three separate grades

UTQG stands for Uniform Tire Quality Grading. The federal rule behind it, 49 CFR 575.104, requires tire makers and brand owners to give information on the relative performance of passenger car tires in three areas: treadwear, traction and temperature resistance. Its stated purpose is to help buyers make an informed choice.

The three grades answer three different questions. Treadwear is about relative wear. Traction is about wet braking. Temperature is about how well the tire resists building up heat and gets rid of it. There is no overall score, and adding the three together doesn’t make one.

Treadwear: a number

The treadwear grade is a comparative rating based on how fast the tire wore on a government test course near San Angelo, Texas, under controlled conditions. The rule gives an example: a tire graded 150 would wear one and a half times as well on that course as a tire graded 100. Grades are set in steps of 20.

The same rule warns that real results depend on how the tire is used and “may depart significantly from the norm” because of driving habits, service practices, road characteristics and climate. A treadwear grade isn’t a mileage promise. Read more on treadwear vs. mileage.

Traction: AA, A, B or C

Traction grades, from highest to lowest, are AA, A, B and C. They show the tire’s ability to stop on wet pavement, measured on government test surfaces of asphalt and concrete. In the rule’s own words, a tire marked C “may have poor traction performance”.

The test is straight-ahead braking only. It does not cover acceleration, cornering, hydroplaning or peak traction. More on traction grades.

Temperature: A, B or C

Temperature grades are A (highest), B and C. They show the tire’s resistance to generating heat and its ability to dissipate heat on an indoor laboratory test wheel. C is the level all passenger car tires must meet under Federal Motor Vehicle Safety Standard No. 109; B and A are higher levels on the test wheel.

The grade assumes a tire that is properly inflated and not overloaded. The rule warns that excessive speed, underinflation or excessive loading, alone or together, can cause heat buildup and possible tire failure. More on temperature grades.

Tires without UTQG grades

The rule does not apply to every tire. It excludes deep tread winter-type snow tires, space-saver or temporary spare tires, tires with rim diameters of 12 inches or less, and certain limited-production tires. A missing grade on those tires is not a low grade. It just means the rule doesn’t cover them.

How to use the grades on this site

On TreadwearRatings you can filter tire lines by all three grades, compare up to four lines side by side, and browse rankings. Treat the grades as one input among several. They describe standard tests, not how a tire will do on your car.

Source

All facts on this page come from the federal rule, 49 CFR 575.104 (Uniform tire quality grading standards). The grades listed on this site come from NHTSA’s published UTQG ratings data (see our data source page).