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Basics

All about tires: sizes, types, pressure and when to replace

The only contact your car has with the road — learn to read a tire, choose the right type and keep it safe.

Aug 17, 2026 ✔ Free
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Reading a tire size

205/55 R16 means: 205 mm section width, 55% aspect ratio, R radial, 16-inch rim. After the size come the load index (91) and speed index (V) — never fit a lower load index than original.

Types of tires

  • Summer: best grip above 7 °C, longer life
  • Winter: soft compound for cold, snow and ice
  • All-season: a compromise, weakest at both extremes
  • Performance: sticky compound, shorter life, more noise

Pressure — the free fuel saver

Under-inflation raises consumption 2–3%, wears the edges and overheats the tire. Check cold monthly and before long trips. Use the door-sticker pressure, not the one on the tire wall.

When to replace

  • Tread below 1.6 mm (many replace at 3 mm)
  • Bulges, cuts or exposed cords
  • Cracks in the sidewall
  • Uneven wear — get an alignment
  • More than 6–10 years old regardless of tread
  • After a bad impact or blowout

Questions about this article

Fitting new tires to the rear is often recommended, even on front-wheel-drive, to keep the rear stable. Never mix different sizes or drastically different tread across an axle.
Yes — every 8,000–12,000 km per the manual evens out wear and extends life. Follow the pattern for your drivetrain.
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