Before you begin. This procedure is general reference information, not professional advice. Equipment varies by manufacturer, model, and year. Always follow the documentation supplied with your equipment — where it differs from this page, follow the manufacturer. Verify that you have the tools, the working conditions, and the ability to do this task safely. If anything is unclear, if the equipment is damaged, or if the task exceeds your experience, stop and use a qualified professional. You are responsible for your own safety and for the outcome. This site accepts no liability for any loss, damage, or injury arising from the use of this information.
Specifications marked unverified could not be traced to a manufacturer source. Do not rely on them — obtain the value from your equipment documentation.
Summary
Most passenger car tires sold in the United States carry three federal grades moulded into the sidewall: a TREADWEAR number, a TRACTION letter and a TEMPERATURE letter. Together they make up the Uniform Tire Quality Grading System, or UTQG, created by 49 CFR 575.104. This page shows exactly where to find each grade and what each one measures, using the wording of the regulation itself and NHTSA's own consumer material.
It will not tell you which grade to buy, and it will not tell you that a number on one brand of tire means the same thing as the same number on a different brand. Under the regulation, it is each tire's own manufacturer or brand name owner that tests the tire and assigns its grades; NHTSA sets the test procedure and can audit the result, but does not grade every tire itself before it reaches a shelf. None of the government sources this page cites states that a grade from one manufacturer reads straight across against a grade from another manufacturer, so this page does not make that claim either.
Necessary equipment
| Item | Note |
|---|---|
| Flashlight optional | A flashlight helps you read a mark in low light. |
| Cloth optional | A cloth clears dirt from marks on the sidewall. |
| Pen and paper optional | Record the grades for each tire. |
Specifications
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
Find the grades on the tire
Estimated under a minute
No tier-1 source was found for this value. Take it from the documentation supplied with your equipment.
- Find the sidewall of the tire.<1mReport a problem with step 1, Find the grades on the tire
- Find the area between the tread shoulder and the widest point of the sidewall.<1mReport a problem with step 2, Find the grades on the tire
- Federal regulation calls that widest point the maximum section width.
- Find the words TREADWEAR, TRACTION and TEMPERATURE moulded into that area.<1mReport a problem with step 3, Find the grades on the tire
Read the treadwear grade
Estimated under a minute
DO NOT COMPARE THE TREADWEAR NUMBER OF ONE MANUFACTURER AGAINST THE TREADWEAR NUMBER OF A DIFFERENT MANUFACTURER.
The tire's own manufacturer, or its brand name owner, tests it and sets its grade.
- Read the number after the word TREADWEAR.<1mReport a problem with step 1, Read the treadwear grade
- The number is a grade for tread life, not a distance in miles.
- A test convoy on a government course sets the number, in steps of 20.
Read the traction grade
Estimated under a minute
DO NOT USE THE TRACTION GRADE AS A RATING FOR CORNERING, ACCELERATION OR HYDROPLANING.
The government test measures only straight-line braking traction on wet pavement.
- Read the letter after the word TRACTION.<1mReport a problem with step 1, Read the traction grade
- The four grades, from highest to lowest, are AA, A, B, and C.
- The letter shows the tire's ability to stop on wet pavement in a government test.
Read the temperature grade
Estimated under a minute
DO NOT DRIVE WITH LOW TIRE PRESSURE, WITH EXCESS LOAD, OR AT EXCESS SPEED.
Heat can increase in the tire and cause it to fail. A tire failure at speed can cause a crash and injure you.
- Read the letter after the word TEMPERATURE.<1mReport a problem with step 1, Read the temperature grade
- The three grades, from highest to lowest, are A, B, and C.
- The letter shows the tire's ability to hold and release heat in a government test.
- Grade C is the lowest grade that federal law allows for sale.
Tires that do not carry a grade
Estimated under a minute to 1 min
- If the tire has no TREADWEAR, TRACTION or TEMPERATURE mark, read the exemptions below.<1mReport a problem with step 1, Tires that do not carry a grade
- A deep-tread, winter-type snow tire is exempt.
- A space-saver or temporary spare tire is exempt.
- A tire with a rim diameter of 12 inches or less is exempt.
- A small-volume tire that meets the federal limited-production test is exempt.
Record the grades
Estimated 1 min to 2 min
- Record the treadwear number, the traction letter and the temperature letter.<1mReport a problem with step 1, Record the grades
- Do the same steps for each tire on the vehicle and for the spare tire.<1mReport a problem with step 2, Record the grades
- Keep the record with your vehicle documentation.<1mReport a problem with step 3, Record the grades
Terminology
This page uses one term for each item and holds it throughout, as ASD-STE100 requires. Equipment sellers and other guides use the names below for the same parts.
- Uniform Tire Quality Grading System
- Also called: UTQG, UTQGS, tire quality grade, DOT tire grade, treadwear traction temperature rating
- treadwear grade
- Also called: tread wear rating, treadwear number, tire mileage rating, how long will these tires last
- traction grade
- Also called: traction rating, wet traction grade, AA A B C tire rating
- temperature grade
- Also called: heat resistance rating, tire temperature rating, tire heat rating
- course monitoring tire
- Also called: control tire, reference tire, CMT, standard reference test tire
- brand name owner
- Also called: private label tire brand, store brand tire, house brand tire
When to use a professional
Speak to a tire dealer for a grade recommendation for this vehicle or this climate. This page does not name a required grade for your vehicle. Only your vehicle documentation and a tire dealer give that.
Speak to a tire dealer if the tire has a cut, a bulge or a crack. This page does not cover tire condition or tire safety.
Common questions
What do the numbers and letters on a tire's UTQG label mean?
They are three separate federal grades required on most passenger car tires: a TREADWEAR number, a TRACTION letter and a TEMPERATURE letter, all moulded into the sidewall between the tread shoulder and the tire's widest point. Federal regulation 49 CFR 575.104 created this system, called the Uniform Tire Quality Grading System or UTQG, so a shopper has some government-standardized information to compare tires by. The treadwear number is a wear-rate index, the traction letter is a wet-braking grade, and the temperature letter is a heat-resistance grade, and each measures something different, so none of the three substitutes for either of the other two.
What does the treadwear number on a tire mean?
It's a comparative wear-rate index, not a mileage figure. NHTSA's own required wording, which every manufacturer must restate on request, says a tire graded 150 'would wear one and one-half times as well on the government course as a tire graded 100.' The number comes from a real test: a convoy of vehicles drives the candidate tire and a standardized reference tire around a roughly 400-mile government course, and the number is set in steps of 20. The same federal wording adds a caution worth keeping: real-world wear 'may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate.'
Can I compare treadwear numbers between different brands of tires?
Treat that comparison with caution. Under the regulation, it is each tire's own manufacturer or brand name owner, not an independent government lab, that tests the tire and assigns its grade; NHTSA sets the test procedure and can audit a manufacturer's result, but does not grade every tire that reaches a shelf. NHTSA's own published interpretation of the rule confirms that a manufacturer 'may exercise a considerable degree of discretion as to the amount of testing necessary' before it assigns a grade. None of the government sources this page draws on states that a treadwear number from one manufacturer is directly comparable to the same number from a different manufacturer, so this page does not make that claim either; a comparison within one manufacturer's own tire line rests on firmer ground.
What do the AA, A, B and C traction grades mean?
They grade how well a tire stops in a straight line on wet pavement, from AA (highest) down to C (lowest), in a government test on asphalt and concrete test surfaces. Federal regulation is explicit about what the grade leaves out: it 'is based on straight-ahead braking traction tests, and does not include acceleration, cornering, hydroplaning, or peak traction characteristics.' Federal regulation warns that a tire graded C may have poor traction performance. C is the lowest of the four grades, and the regulation does not describe any grade as passing or failing — so read C as the bottom of the scale, not as a verdict either way.
What do the A, B and C temperature grades mean?
They grade how well a tire resists heat and sheds it, from A (highest) down to C (lowest), in a government indoor test. Grade C is not a failing grade: federal law requires every passenger tire to reach at least that level under Federal Motor Vehicle Safety Standard No. 109, so grades B and A represent performance above the legal minimum, not the only acceptable results. The grade itself carries a federal warning worth repeating: it 'is established for a tire that is properly inflated and not overloaded,' and excess speed, low pressure or excess load can build heat in a tire and lead to failure.
Where on the tire are the UTQG grades printed?
Between the tread shoulder and the tire's maximum section width, its widest point, moulded permanently into the sidewall, under 49 CFR 575.104. Some new tires also carry a temporary label on the tread itself with the same information; that label is meant to wear off with use, and the sidewall marking is the permanent one.
Why doesn't my tire have TREADWEAR, TRACTION or TEMPERATURE grades?
A handful of tire types are exempt from the whole UTQG requirement: deep-tread winter or snow tires, space-saver or temporary spare tires, tires with a rim diameter of 12 inches or less, and some low-volume tires that meet a federal limited-production test. If your tire does not fall into one of those categories and still carries no grade, ask the seller or the manufacturer directly.
Related procedures
- How to check tire tread depth and know when you need new tires
- How to read a tire sidewall and find out how old your tires are
- How to check if your spare tire is there, in good shape and has enough air
- How to check your tire pressure and put the right amount of air in your tires
- What the tire pressure light on my dashboard means and what to do about it
- How to check the tire sealant and inflator kit your car carries instead of a spare tire
- How do I check that my lug nuts (wheel nuts) are still tight after a tire shop, a mobile fitter, or a roadside wheel change?
Sources
Every specification on this page is traced to one of these sources. Tier 1 is a manufacturer document, a published standard, or a government safety authority. See Standards for the full tiering rule.
- Tier 149 CFR 575.104 — Uniform tire quality grading standards
- Tier 1Tire Safety Ratings and Awareness (TireWise)
- Tier 1NHTSA Interpretation Letter to Uniroyal Tire Company, 1980-09-18 — UTQG treadwear grading test data
Revision history
Current version 2 · updated 2026-08-04 · next review due 2027-08-04
- v2 · 2026-08-04FAQ 4 called grade C 'the lowest passing grade'. 49 CFR 575.104 ranks the grades AA, A, B, C from highest to lowest and warns that a tire marked C may have poor traction performance; it never frames the scale as pass-or-fail. 'Passing' was the page's own word and it reads as reassurance the regulation does not give. Replaced with what the regulation says.
- v1 · 2026-08-04First draft, scaffolded as a reference record on backlog guidance. Built directly from 49 CFR 575.104, read in full through the eCFR versioner API (www.ecfr.gov itself redirects an automated request to a block page), and from NHTSA's TireWise consumer page and a 1980 NHTSA Chief Counsel interpretation letter on manufacturer discretion in UTQG testing. The backlog entry's working claim was that treadwear grades are self-assigned relative to a control tire the manufacturer itself picks, so grades compare only within one brand and never across brands. Direct reading of 575.104 complicates the second half of that claim: the course monitoring tire is a single ASTM F2493 standard reference tire with a government-measured base wear rate, not a tire each manufacturer separately selects, so the regulation's own test structure is more standardized than the popular framing suggests. What IS directly supported by the sources read for this record is the self-certification structure itself (each manufacturer or brand name owner tests and grades its own tire) and NHTSA's own confirmation that a manufacturer has real discretion in how much testing it does. No source read for this record states outright that treadwear numbers ARE or ARE NOT numerically comparable across manufacturers, so the record states only what is sourced and is explicit, in the summary and in one FAQ answer, about what it does not claim. Every specification publishes as consult-the-manufacturer; nothing is marked verified because this session cannot write data/specs.json. Sources staged in data/sources-additions-read-the-utqg-treadwear-traction-and-temperature-grades.json; nhtsa-tirewise was already registered in data/sources.json and is cited as-is.
Corrections to this page are listed in the public corrections log. Reports that are credible and not yet verified are listed in the public errata register, and an open one renders above the step it concerns.
Comments and corrections
Found an error? A correction with a manufacturer source is applied and logged publicly. You can also write to corrections@fixchecklist.com.
Every step above carries its own report control, which tags the report with that step so a correction reaches the right place. For anything about the procedure as a whole — the order of the sections, a step that is missing, something that did not match your equipment — use this: report something about this whole procedure.