Tyres and the Law

European Regulations — "E" Marking

Radial car and 4x4 tyres are type approved in accordance with ECE regulations, and carry the requisite mark on the tyre’s sidewall, for example, E3 0162.

Consumer protection regulations prohibit the sale of car radial or 4x4 tyres which are not "E" marked.

Minimum Legal Tread Depth

The main reason a tyre has tread is to disperse water efficiently. The less tread you have, the more likely you are to skid or aquaplane on wet roads and lose steering control.

It is illegal to run a tyre with less than 1.6mm of tread round the entire outer circumference of the tyre. Tyre manufacturers build a number of tread wear indicator bars into the tread area of their tyres which become visible at 1.6mm. These serve as a useful visual reminder to change your tyres.

However, wet weather braking and cornering efficiency reduce considerably as the tyre wears down and we strongly advise that you change your tyres before you reach the legal limit.

The penalty for driving with illegal tyres on your car is very severe. There is a compulsory driving licence endorsement of three penalty points and a fine of up to £2,500 for each illegal tyre.

Relative stopping distances of tyres (not to scale)

Getting the most from your tyres

Keep the Pressure Up

The right tyre inflation pressure for your car can be found in the car manufacturer's handbook. Most tyre manufactures also supply correct pressure and fitment details for their tyres. Tyre pressures relate to loads, speeds and vehicle handling and the right tyre pressure is vital for even braking, maximum grip and good tyre life.

Inflation pressure should be checked at least once a fortnight when the tyre is cold since there is an increase in pressure when the tyre has warmed up after being run. A reliable pressure gauge should always be used.

It is dangerous to re-inflate a tyre which has been run flat or seriously under-inflated and such tyres should be removed and inspected by a tyre specialist.

Wheel Alignment

The correct tracking or alignment of your wheels is important as it greatly increases the life of you tyres by avoiding excessive wear on one side of the tread. Because the right tracking or alignment also improves the handling of your vehicle, you will be more comfortable.

Age Deterioration

Tyres can deteriorate with age which shows as cracking of the tread and sidewall rubber. Cracking is usually an indication that tyres have been in service an extremely long time.

If cracking is severe the tyre must be replaced. Tyres fitted to caravans and boat trailers which are parked for long periods of time, particularly in coastal regions, will tend to age and crack more quickly than those which are used and run frequently.

Punctures and Repairs

Repairs to tyres and tubes must be carried out to meet the British Standard AU 159 and should always be entrusted to a specialist. Essentially, this means plugging a hole, not patching over it.

All punctured or damaged tyres should be removed from the wheel for internal and external examination to ensure that there is no hidden damage that could cause a later failure.