Do tyres deteriorate with age?

Tyre ageing and deterioration

Yes, tyres deteriorate with age. This is a natural process that affects all rubber products, regardless of whether the tyre has been used or stored.

What causes deterioration

• Oxidation — Oxygen reacts with the rubber over time, causing it to harden and lose flexibility
• UV exposure — Sunlight breaks down the rubber compound at the molecular level
• Ozone — Atmospheric ozone attacks the rubber surface, causing surface cracking
• Heat — Exposure to high temperatures accelerates all of the above processes

What this means in practice

Aged tyres have reduced grip, are more prone to cracking, and carry a higher risk of sudden failure. This applies even to tyres that have been stored indoors and never fitted to a vehicle. Always check the DOT manufacture date on the sidewall and follow the replacement guidelines of 5 to 6 years maximum, or 10 years absolute limit.