Correct Inflation Pressure
Inflation pressure is important, as the pressurised air inside your tyre has to support the weight of your vehicle and its load. Tyre pressures may vary depending on the vehicle model and the load being carried.
We recommend that you check your tyre pressures regularly against the manufacturer’s specifications for your vehicle (refer to your owners handbook) at your local service station.
Wheel Alignment & Balancing
You may hear the terms ‘wheel alignment’ and ‘wheel balancing’ used interchangeably, but they are separate issues, both important in the upkeep of your tyres and vehicle.
Wheel alignment consists of adjusting the angles of the wheels so that they are perpendicular to the ground and parallel to each other. Aligning your wheels can help maximise tyre life and ensure that your vehicle drives straight and true when on level surfaces.
The symptoms of a misaligned wheel include:
- uneven or rapid tyre wear
- pulling or drifting away from a straight line
- drifting on a straight, level road
- spokes of the steering wheel tending toward one side while driving on a straight, level road
Wheel balancing allows the tyres and wheels to spin without causing any vibrations. Your wheels’ balance is gauged by checking for any heavy spots on the wheel-tyre combination and compensating for such flaws by placing a measured balancing weight on the opposite side of the wheel from where the heavy spot is located.
The symptoms of a wheel that is out of balance include:
- vibration in the steering wheel, seat or floor-pan, usually at motorway speeds
- ‘scalloped’ or ‘cupped’ wear pattern on the tires
If your tyres demonstrate any of the symptoms outlined above, we advise that you seek advice from your local authorised tyre repair centre.
Tyres displaying signs of deterioration should be removed and not used on the road.
There are several signs of deteriorating tyres you should keep an eye out for:
- cracking/crazing of the side wall of the tyre, caused by its flexing
- distortion of the tyre tread
- deformation of the main body of the tyre
- persistent loss of inflation pressure
- deep cuts
- separated or perished rubber
- vibrations through the tyres when you drive
Tyres showing any of these signs of wear should be investigated by a qualified tyre specialist, such as a tyre dealer, as soon as possible to assess the tyres’ suitability for continued service.
Further information on how tyres are checked on vehicles at their roadworthiness test is available in the NCT testers manual (PDF), LGV test manual(PDF) and HGV test manual (PDF).
Tyres more than 10 years old, including spare tyres, should be replaced—even if such tyres appear serviceable and even if they have not reached the legal tread wear limit of 1.6mm. This recommendation does not in any way reduce your responsibility to change tyres that are worn or damaged.
When a tyre has been in use, the effects of aging are lessened to a degree, so tyres that have been in storage should not be placed into use if more than six years old.
The effects of aging may be brought on prematurely, depending on such factors as load, speed, inflation pressure and maintenance. Premature aging may also occur in tyres that are:
- stored and later used as spare wheels.
- used on caravans and trailers. If caravans or trailers are not in regular use, their tyres should be inspected before every journey.
- used predominantly in coastal areas, due to the saline conditions.
- cleaned with certain chemical products.
How can I tell the age of my tyres?
The date of manufacture can be determined by the serial number located on the tyre sidewall. The serial number is a code usually preceded by the acronym ‘DOT’.
The last four digits of the serial number refer to the date of manufacture. As shown in the image the first two numbers indicate the week of manufacture (ranging from ‘01’ to ‘52’), while the last two numbers indicate the year of manufacture.