When to replace tyres, and how to read the date on them

Tyres are the only part of a car that touches the road, and they are the part people leave longest. Four things decide whether yours have had it.

Here is what that means in practice:

1. Tread depth, across the whole tyre

1.6mm is the law across the central three quarters. Braking distances in the wet grow sharply under 3mm, which is where we start telling people to budget for a pair.

2. The date code

Four digits inside an oval on the sidewall: week, then year. 3419 is the 34th week of 2019. Rubber hardens whatever the mileage, and anything past about ten years should be replaced even if it looks new.

3. How the wear is spread

Worn in the middle means over-inflation, worn on both shoulders means under-inflation, worn on one shoulder means alignment. Fitting a new tyre without fixing the cause buys you the same problem next year.

4. Damage you can see

Bulges in the sidewall are a tyre that has already been hurt by a kerb or a pothole. They do not heal and they fail suddenly.

We fit tyres in the common sizes while you wait, and we will always tell you when two will do and four are not needed.