What does UTQG 600 A A mean?

Treadwear 600, traction grade A, temperature grade A. Treadwear 600 means the tire wore at a sixth of the rate of the reference tire on the government test course. Traction A means it exceeded 0.47 on wet asphalt and 0.35 on wet concrete under the locked wheel test. Temperature A means it handled heat above 115 mph on the laboratory test wheel.

What is the highest traction grade?

AA. The grades run AA, A, B, C from highest to lowest, and a grade is defined by exceeding a threshold on BOTH the wet asphalt and the wet concrete test surface, not one of them.

UTQG: treadwear, traction and temperature

Three grades, set by a federal regulation, each measuring something narrower than its name suggests. The thresholds below are the regulation's own numbers.

Treadwear

A comparative number, not a mileage. A tire graded 200 wore at half the rate of a tire graded 100 on the government test course under test conditions. It is not a promise of twice the miles, and it is not comparable across brands with confidence: manufacturers run their own tests and assign their own grades, and are only forbidden from overstating them. Treat it as a within-brand comparison and nothing more.

The number is a ratio against a course monitoring tire graded 100, measured on a fixed test course. It is not a mileage warranty, it is not independently verified, and it is at its least reliable when comparing across brands.

Traction

Straight ahead braking on wet asphalt and wet concrete, with the wheel locked, at 40 mph. That is the whole test. It says nothing about cornering, hydroplaning, dry grip, acceleration or snow, and the regulation prints that warning itself.

UTQG traction grades and their adhesion coefficients
Grade	Wet asphalt	Wet concrete	Sources
AA	more than 0.54	more than 0.38	3
A	more than 0.47	more than 0.35	3
B	more than 0.38	more than 0.26	3
C	0.38 or less	0.26 or less	3

A grade requires exceeding the threshold on BOTH surfaces, not either one. Grade C is defined the other way round: at or below the B thresholds.

Temperature

Resistance to heat build up, measured on an indoor laboratory test wheel rather than on a road. Grade C is the minimum a passenger tire must meet to be sold in the United States, so there is no D. The grade assumes the tire is correctly inflated and not overloaded; underinflation or overloading undoes it.

UTQG temperature grades and their speed bands
Grade	Heat handled at	Sources
A	above 115 mph	3
B	100 to 115 mph	3
C	85 to 100 mph	3

There is no D grade. C is the minimum a passenger tire must meet to be sold in the United States, so a tire that cannot reach C cannot be sold at all.

Not every tire carries these

UTQG grades are not required on every tire. Deep tread light truck tires, winter and snow tires, temporary spares, trailer tires and tires under 12 inches are among the exemptions, so an absent grade is not a defect.

Common questions

What does UTQG 600 A A mean?: Treadwear 600, traction grade A, temperature grade A. Treadwear 600 means the tire wore at a sixth of the rate of the reference tire on the government test course. Traction A means it exceeded 0.47 on wet asphalt and 0.35 on wet concrete under the locked wheel test. Temperature A means it handled heat above 115 mph on the laboratory test wheel.
Is a higher treadwear number always a longer lasting tire?: A comparative number, not a mileage. A tire graded 200 wore at half the rate of a tire graded 100 on the government test course under test conditions. It is not a promise of twice the miles, and it is not comparable across brands with confidence: manufacturers run their own tests and assign their own grades, and are only forbidden from overstating them. Treat it as a within-brand comparison and nothing more.
What is the highest traction grade?: AA. The grades run AA, A, B, C from highest to lowest, and a grade is defined by exceeding a threshold on BOTH the wet asphalt and the wet concrete test surface, not one of them.
What does the temperature grade actually measure?: Resistance to heat build up, measured on an indoor laboratory test wheel rather than on a road. Grade C is the minimum a passenger tire must meet to be sold in the United States, so there is no D. The grade assumes the tire is correctly inflated and not overloaded; underinflation or overloading undoes it.
Why does my tire have no UTQG grades?: UTQG grades are not required on every tire. Deep tread light truck tires, winter and snow tires, temporary spares, trailer tires and tires under 12 inches are among the exemptions, so an absent grade is not a defect.

Where these figures come from

Published values here were read from 4 independent sources:

49 CFR 575.104 - Uniform tire quality grading standards - Legal Information Institute, Cornell Law School, current text read 27 August 2026 (read 2026-08-27)
Traction grade adhesion coefficients, traction and temperature grade definitions, treadwear grading procedure
Uniform Tire Quality Grading - Wikipedia, revision read 27 August 2026 (read 2026-08-27)
Traction grade g force table, temperature grade speeds, treadwear grade meaning and limits
UTQG Ratings Explained - TireGrades, updated 9 March 2026 (read 2026-08-27)
Traction grade g force table, temperature grade speeds, treadwear self reporting
UTQG - How to Read a Sidewall - Yokohama Tire, undated manufacturer reference (read 2026-08-27)
Temperature grade speeds, which tire categories are exempt from UTQG marking

These are independent publishers, not independent measurements. Each one reproduces a table originally set by a standards body, so agreement between them shows a value was transcribed correctly, not that the underlying table is right. Where a figure is safety relevant, check it against the tire manufacturer's own data before relying on it.