Car Tyres, Are Your Tyres Safe?

Cars are by far the most common vehicles on Britain’s roads so it’s no surprise they are involved in the highest number of tyre-related incidents. Simple maintenance can help avoid a large proportion of these incidents and keep drivers and other road users safer.

Car Tyres and Your Safety

Tyres are the only parts of the car which are in contact with the road. Safety in acceleration, braking, steering and cornering all depend on a relatively small area of road contact. It is therefore of paramount importance that tyres should be maintained in good condition at all times and that when the time comes to change them the correct replacements are fitted.

The original tyres for a car are determined by joint consultation between the car and tyre manufacturers and take into account all aspects of operation. It is recommended that changes in tyre size or type should not be undertaken without seeking advice from the car or tyre manufacturers, as the effect on car handling, safety and clearances must be taken into account.

In some other European countries it is illegal to use replacements which differ in certain respects (e.g. size, load, and speed rating) from the tyre fitted originally by the vehicle manufacturer. Tyres are a high-tech composite product, the result of over 100 years of continuous development. The overwhelming majority of tyres on the road today are of radial construction.

Some tyres, known as Self Supporting Run Flat tyres, are designed to provide a limited run on period following a puncture.

Why is tyre maintenance so importance, and how should I check my tyres?

Tyres are the only parts of the car which are in contact with the road. Safety in acceleration, braking, steering and cornering all depend on a relatively small area of road contact. It is therefore of paramount importance that tyres should be maintained in good condition at all times and that when the time comes to change them the correct replacements are fitted. There are several simple and basic checks that can be performed at home to check air pressure, condition and tread (A.C.T)

The Checks

Should I change my vehicle’s tyre size or type?

The original tyres for a car are determined by joint consultation between the car and tyre manufacturers and take into account all aspects of operation. It is recommended that changes in tyre size or type should not be undertaken without seeking advice from the car or tyre manufacturers, as the effect on car handling, safety and clearances must be taken into account. In some other European countries it is illegal to use replacements which differ in certain respects (e.g. size, load, and speed rating) from the tyre fitted originally by the vehicle manufacturer. Tyres are a high-tech composite product, the result of over 100 years of continuous development. The overwhelming majority of tyres on the road today are of radial construction.

How often should I inspect my tyres?

Tyres should be inspected at least monthly for punctures, cuts, bulges, cracking or any other abnormal visual indications. Particular attention should be paid to tyres that are used infrequently; for example as fitted to spare wheels, trailers, caravans and specialist or collector’s vehicles. Tyres should be examined frequently, removing stones or other embedded objects from the tread. You should look for lumps and bulges, and any oil or grease which should be removed using a suitable detergent.

What if I find a lump or bulge in my tyre?

If when inspecting your vehicle’s tyres you discover a lump or bulge it must be examined by a tyre specialist since these could indicate internal damage.

How do wet conditions or roads affect tyre grip?

Tyre treads are designed to give good grip on wet roads but in general wet grip decreases as the tyre tread depth approaches the legal minimum. Motorists should take this into consideration and reduce speed when driving in wet conditions. For the same reason motorists may wish to consider replacing tyres before the tread depth reaches the legal minimum.

What is the legal minimum tread depth in the UK?

The legal minimum tread depth in the UK is 1.6mm across a continuous band comprising the central three-quarters of the breadth of tread and round its entire circumference.

What do I need to do if I hit a pot-hole or the kerb?

Driving over pot-holes, kerbs, etc, even at low speed, can result in the weakening or fracture of the tyre’s inner structure. It may be dangerous to re-inflate a tyre which has been run flat or seriously under inflated and such tyres should be removed for comprehensive examination by a tyre specialist.

What should I do if I notice noises or vibrations from a tyre whilst driving?

It is important to be attend to unusual noises or vibrations from a tyre whilst driving as quickly as is practically possible. If you discover or suspect any degradation it is strongly advised to have the tyre inspected as soon as practicable by a tyre service professional. Some tyre and vehicle manufacturers make recommendations regarding the maximum age of tyres in use. This guidance should always be respected.

Does my tyre need to be fitted in a certain direction?

It depends on the type of tyre. Some tyres have patterns where the direction of rotation is important to achieve their full performance. These are known as ‘Directional’ pattern tyres and the direction of rotation is marked on the sidewall. Equally, some tyres have patterns which are different on the inner half of the tread compared to the outer half. These ‘Asymmetric’ tyres have their sidewalls marked ‘Outside’ and/or ‘Inside’ or similar wording. It is important with both these types of tyre to observe the fitting markings on the tyre sidewall. In the case of Directional tyres if the spare wheel is used it may be necessary to have the tyre reversed on the rim as soon as conveniently possible after deployment.

How long will a new set of tyres last?

Whilst tyres are designed and manufactured to give long service under typical operating conditions, for most tyres, replacement will ultimately be triggered by tread wear. However, adverse environmental, operational or storage conditions can make replacement necessary before the tread is worn to the legal limit.

How can I tell how old a tyre is?

Tyres carry a date code moulded into the sidewall. On one side of the tyre there is a 12-character code often marked “DOT”. For tyres manufactured after 1999 the last four digits of the code represent the week number and the year of manufacture. For example, a tyre marked XXXX XXXX 3712 was made in week 37 of 2012.

Do I need a specialist tyre for my vehicle?

Some tyres are marked for specific vehicle manufacturers e.g. Mercedes or BMW. In most cases, this does not prohibit the tyres from being fitted to any other vehicle, or from non-marked tyres being fitted to the vehicle, but can be used as a guide to identify the homologated specification. For high performance cars, the specific tyre should be fitted to the vehicle e.g. Porsche or Ferrari. Consult the vehicle handbook or the tyre manufacturer if in any doubt.

Related content

Tyre Pressure Monitoring System

Such is the importance of correct tyre inflation on passenger vehicles, TPMS is regarded as an important safety feature.…

The Checks

Learn about the checks which will help you reduce the risks of a tyre-related incident out on the roads.Welcome to…

Buying advice

Many drivers buying part worn tyres do so in the belief that they offer better value for money when compared with new…

Campaigns

TyreSafe campaigns to raise awareness of regular tyre safety checks to reduce the risk of tyre related incidents on the…