Tire guides
What these are: 10 short guides on the questions behind the numbers: what treadwear means, why warranty miles aren’t mileage, when to replace, how to compare cost per mile. Each one opens with the answer, cites the pages it relies on (NHTSA, 49 CFR, the Tire Industry Association, USTMA, makers), shows the date it was last updated, and links to the matching size and line pages.
UTQG basicsWhat does a tire treadwear rating mean?A treadwear grade is a relative wear-rate number.Updated 2026-10-25 · 5 sourcesTreadwear vs. mileageTreadwear rating vs. mileage warrantyNeither is a prediction of how long your tires will last.Updated 2026-10-25 · 5 sourcesTire sizesHow to read a tire sidewallIn P225/60R16 97V: P = passenger tire, 225 = section width in millimeters, 60 = sidewall height as a percent of width, R = radial, 16 = wheel diameter in inches, 97 = load index and V = speed symbol.Updated 2026-10-25 · 6 sourcesBuying mathHow to calculate tire cost per mileDivide the total you pay for a set by the miles you expect to get from it.Updated 2026-10-25 · 3 sourcesSafetyWhen to replace your tiresReplace tires when the tread is worn to 2/32 of an inch (wear bars level with the tread, or the top of Lincoln’s head visible in the penny test), when you see damage such as bulges or exposed cord, and ask a professional about tires that are six to 10 years old even if the tread looks fine..Updated 2026-10-25 · 5 sourcesUTQG basicsTire traction and temperature grades explainedTraction grades (AA, A, B, C) rank a tire’s straight-ahead braking on wet asphalt and concrete skid pads; temperature grades (A, B, C) rank resistance to heat build-up on a lab test wheel.Updated 2026-10-25 · 4 sourcesTire typesAll-season vs. all-weather vs. winter tiresAll-season tires cover moderate climates and usually carry M+S but not the three-peak mountain snowflake (3PMSF).Updated 2026-10-25 · 6 sourcesMaintenanceHow to make your tires last longerKeep pressure at the vehicle’s placard value (check monthly with tires cold), rotate on the schedule in your owner’s manual (industry guidance is every 5,000–8,000 miles), and get alignment and balance checked when the car pulls or vibrates.Updated 2026-10-25 · 5 sourcesBuyingHow much do tires cost?It depends mainly on your size, the tire’s speed and load ratings, its type and maker, and your installer’s fees, so there is no single honest number.Updated 2026-10-25 · 4 sourcesChoosingHow to find the longest-lasting tires for your sizeNo public number predicts your mileage, so triangulate: shortlist your exact size’s lines by NHTSA treadwear grade, compare maker mileage warranties for your speed rating, check test claims for who ran them, then convert to cost per mile.Updated 2026-10-25 · 5 sources
How we write them
- Claims come from pages we actually read, linked at the bottom of each guide. Maker statements are labeled as the maker’s own.
- Numbers from NHTSA’s database are computed at build time from the dataset we publish. Worked examples with invented numbers say so.
- We show no tire prices: we have no licensed price source.
- Corrections go through About. Method: methodology. Updates: Atom feed.