Tyre Age (DOT Date Code)
Tyre age is shown by the four-digit DOT date code on the sidewall, giving the week and year of manufacture.
What is Tyre Age (DOT Date Code)?
For example 2321 means week 23 of 2021. Rubber hardens with age even if tread is good. Many manufacturers suggest inspection after five years. Signs of ageing include fine cracks in the sidewall and between tread blocks. Spare wheels and caravan tyres often age out before they wear out. Storage away from sunlight, heat and ozone sources such as electric motors slows ageing. Some manufacturers recommend replacing tyres at ten years regardless of tread.
How it works
Oxidation and UV light slowly harden the rubber.
Why it matters for your car
Old tyres may crack and lose grip. Check the date when buying tyres.
Other terms
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