Look after your tyres and they will look after you!
They may not always be the first thing you think of when it comes to vehicle safety, bet tyres form the only link between your vehicle and the road. In fact, your safety (and that of your passengers) actually relies on an area of contact between the tyre and the road surface which is no bigger than the palm of your hand - certainly something to bear in mind next time you get behind the wheel! In addition to grip, tyres also support the weight of the vehicle and provide drive and directional control.
The following Michelin checklist outlines a few simple procedures, which if carried out regularly will ensure your tyres remain safe and you get value for money in terms of performance and service life.
Each procedure is then explained in more detail throughout this guide to help you look after you tyres correctly. After all, if you look after your tyres they will look after you!
1 Selection and Fitment
 As a general rule, fit only the tyre size recommended by the vehicle manufacturer. Except for the small of cars that are designed with different tyre sizes for the front and rear, the ideal fitment for optimum performance is always to have identical tyres all round - and this principle becomes even more important at higher speeds. Consult your tyre dealer for fitment details, especially if you are in any doubt.
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2 Visual Tyre Check
By visually checking your tyres on a regular basis you can help maintain them in good condition throughout their service life and prevent having them changed unnecessarily or even failing prematurely. Check all tyres, including the spare, for these points:
• Stones or nails
If not removed when embedded in the tread, stones and nails can work into the casing and cause damage and possible deflation.
• Oil, Fuel or Paint
Oil, fuel or paint can have a harmful effect on the rubber compound used in tyres. Oil can make the tread rubber swell, reducing the pattern grooves and affecting adhesion. Immediate removal with detergent and plenty of water is recommended.
• Damage and Ageing
Any tyre showing signs of damage, such as cuts, bulges, ageing (cracking or grazing), vibration or air loss must be examined by a tyre specialist, as they could be signs of potential tyre failure, even if it is on an un-run or little used vehicle such as a caravan or a motor home. Cracking and crazing occurs naturally through ozone damage and from over exposure of the tyres to the elements, especially sunshine. To reduce this effect, only wash tyres sidewalls when necessary and then just with water, or as little 'car wash' as possible.
• Tyre Service Life
Regular inspection by a tyre specialist is recommended, and tyres which have been in use for 5 years or more should continue to be inspected by a specialist at least annually. Tyres which have been in service for 10 years or more from the dare of manufacturer should be replaced.
For original equipment tyres, also refer to your vehicle manufacturer's recommendations. Please visit www.michelin.co.uk for more information.
• Tyre Tread Wear
Tyre tread wear should be checked regularly. Abnormal wear is an indication of a mechanical anomaly with the vehicle, such as incorrect alignment, or problems with the steering or suspension mechanism. Always have the mechanical parts of the vehicle checked and rectified by a professional.
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3 Tread Depth Selection
 Are your tyres legal? When should you change them?
Always ensure your tyres conform to the UK minimum legal tread depth requirement of 1.6mm, this means your tyres should have at least 1.6mm of tread left across the central three quarters of the tyre tread breadth and around the entire circumference of the tyre.
Various types of tread depth indicator devices can be purchased from car product specialists. These can be dipped into the tyre tread to measure the depth in millimetres.
In addition, most car tyres now have tread wear indicators set into the tread grooves, which show when the tyre is worn to the 1.6mm of remaining tread. When these indicators become level with the tread surface your tyres should be changed immediately. On a Michelin tyre the position of the tread wear indicator is shown by a moulded Michelin Man in the shoulder area.
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4 Tyre Pressure
 Maintaining the correct tyre pressure is an important factor in both the safety and longevity of tyres, because too little or too much air could adversely affect the vehicle handling as well as the tyre's performance and durability. Pressure should be checked using an accurate gauge, available from most petrol stations or from car product specialists.
Make sure of the correct tyre pressures by referring to the vehicle manufacturer's advice, to be found in the handbook, on the door pillar or on the fuel filler cap.
Check tyre pressures monthly and before any long trip. The tyres should be checked when cold, as they heat up as you drive causing a slight increase in pressure. Do not forget to check the spare tyre. If you intend towing with the vehicle, e.g. trailer or caravan, always consult the vehicle handbook or trailer, caravan or tyre manufacturer for suggestions, as increased pressure may be required.
Valves
Ensure that the tyre and wheel combination on your vehicle is fitted with the appropriate valve and valve cap play a very important part in the tyre's ability to maintain air pressure, tyre service life and vehicle safety in general. Whilst the valve does its work of allowing air in and out of the tyre as required, it deteriorates with age and should therefore be changed every time a new tyre is fitted, or if the tyre is removed for repair or examination.
Always use valve caps which have an internal seal that is in good condition. The valve cap retains the air within the tyre and also prevents dirt or grit getting into the valve. Do not over tighten the valve as this can damage the seal and allow any air seeping past the valve to escape from the tyre.
back to top 5 Tyre Positioning and handling
When replacing car tyres the ideal situation would be to replace all four tyres together. However as vehicles wear their front and rear tyres at different rates, this cannot always be done. In this case, Michelin's recommendation is to fit new tyres to the rear and move the part worn rear tyres to the front.  WHY FIT NEW TYRES TO THE REAR?
Primarily to ensure that vehicle stability is maintained in extreme working conditions of hard or emergency braking and cornering. This is especially critical on wet or slippery roads. This also provides additional protection against sudden deflation in the rear tyres which is most likely to cause the loss of vehicle control.
Most modern vehicles being front wheel drive, the front tyres wear faster than the rears. The driver is therefore used to having less grip at the front as the tyres wear towards the replacement. By fitting new tyres to the rear and repositioning the worn tyres on the front axle, the condition the driver has become used to is retained after the tyre change.
4 wheel drive vehicles
We recommend that tyres on 4x4 vehicles are used in identical sets of four. However, the vehicle manufacturers' recommendations should be followed.
DO NOT FORGET:
- If all four tyres are quite worn, consider replacing the full set.
- When moving tyres from one axle to another, pressures should be adjusted to suit the new positions.
- This advice applies to both front and rear wheel drive cars.
- In the case of different front and rear tyre sizes. The advice about moving tyres from one axle to another cannot be applied. However having the least worn tyres on the rear will produce more stable handling characteristics in slippery conditions.
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6 Alignment  Vehicle suspension misalignment can result in rapid, irregular tyre wear, which is bad news for your pocket and can affect the handling and safety of the vehicle.
- If your suspension is misaligned by 4mm (just 2mm per wheel), then for every mile you travel the tyre is being forced sideways by 8.4 metres (28 feet) on a car with 15" wheels.
- With 13" or 14" wheels, 2mm misalignment per wheel will result in even greater tyre scrub. No wonder incorrect alignment results in excessive shoulder wear. Watch out for this when you visually check your tyres.
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