E30 Zone

If a car isn't doing heavy mileage, how long should you run the same rubber. Does it start perishing reardless of remaining tread?

all depends where its kept and how really

In Germany the TUV gives a life of six years, regardless of tread wear. After that, the tyre is scrap. This is valid even if the tyre has been sitting unfitted on a warehouse shelf for most of its life.

The issue is that the chemicals that make up the "rubber" aren't stable; they're affected by changes in temperature as well as UV exposure, and this can make them dry out, stiffen and harden over time, until it comes to crunch time and you need some heavy braking and find out your tyres have turned into Lego plastic.

All tyres have their manufacture date stamped on them as a four-digit code; the first two digits are the week, the last two are the year of manufacture. At present, any tyre stamped 5106 or less is illegal to use in Germany.

Expect this legislation to spread to other EU countries in the very near future.

Thanks that's useful. The car is garaged and primarily used during the summer. The tyres are around 4.5 years old so I'll budget for a new set around 2014.