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Maintenance guide

When to Replace Tires and How to Check Tread

Learn tire replacement intervals, how to inspect tread depth in mm and 32nds of an inch, and when to replace tires for safety and legal compliance.

There is no single kilometer or mileage number that fits every driver. A set can wear out anywhere from 30,000 to 60,000 km (19,000 to 37,000 miles), but aggressive driving, hard braking, heavy loads, low tire pressure, and alignment problems all shorten that life. Age matters too, because rubber hardens and cracks over time even when the tread still looks acceptable.

  1. 1

    Step 1

    1. Check the tire sidewall for the DOT date code. The last four digits show the week and year of manufacture — for example, 2322 means the 23rd week of 2022. As a tire approaches 6 years old, inspect it more carefully, and plan replacement before it reaches 10 years regardless of tread.

  2. 2

    Step 2

    2. Measure tread depth in several places across each tire. The legal minimum is 1.6 mm (2/32") in most of Europe and much of the US, though some regions require more for winter tires — check your local rules. Many safety experts suggest replacing well before that, around 3 mm (4/32"), and immediately once the wear bars sit flush with the tread.

  3. 3

    Step 3

    3. Inspect for cracks, bulges, cuts, exposed cords, or uneven wear. Sidewall damage, bubbles, and repeated punctures mean the tire is no longer reliable even if the tread depth is still decent. When in doubt, have a tire professional assess it.

  4. 4

    Step 4

    4. Compare wear across each axle. If the inner or outer edges are much more worn than the center, check tire pressure and wheel alignment. Uneven wear usually points to a mechanical issue that needs service, not just a replacement tire — fix the cause or the new tire wears out the same way.

  5. 5

    Step 5

    5. Replace tires in pairs, or ideally as a full set, to keep braking and grip balanced. If you fit only one or two, match the size, load index, and speed rating exactly, and put the newest tires on the rear axle for stability in the wet.

Tire condition also matters at periodic vehicle inspections — a US state safety inspection, a UK MOT, a German TÜV/HU, or the EU technical inspection (PTI). A vehicle can fail for unsafe tires, visible damage, or tread below the legal minimum, and requirements vary by country and state. If an inspection is coming up, check your tires in advance so you have time to replace them without a last-minute scramble.

Replacement cost varies widely by tire size, brand, and country, so treat any figure as a rough example only. Fitting, balancing, a new valve, and disposal fees are usually added per tire on top of the tire price. Premium and larger SUV or performance tires cost considerably more, and dealerships generally charge more than independent tire shops.

What tread depth is too low for a tire?
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Once the wear bars sit level with the tread surface, the tire is at the legal limit — 1.6 mm (2/32") in most of Europe and much of the US — and must be replaced. Many experts recommend replacing passenger tires earlier, around 3 mm (4/32"), especially for wet-weather grip.
Can a tire be too old even if it still has tread?
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Yes. Rubber ages, dries out, and loses flexibility over time, regardless of tread depth. If a tire is around 6 years old, inspect it carefully; by about 10 years from the date code, replacement is generally recommended even when the tread still looks usable.
Do I need to replace all four tires at once?
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Not always, but it is the safest option, especially on all-wheel-drive cars. If you replace only two, fit matching tires on the same axle and keep the newer pair on the rear for better stability, braking, and wet-road control.
How often should I check tire tread and pressure?
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Check pressure at least once a month and before long trips, since tires lose pressure naturally and faster in cold weather. Inspect tread and sidewalls every few weeks, and after driving over potholes, curbs, or debris. In hot climates and on rough roads, check more often.