Tyre Maintenace

Tyre Rotation

This means swooping the rear tyres with those in front to tackle the problem of uneven erosion. In front-wheel-drive vehicles, for example, braking, steering and driving forces are concentrated on the front-axle tyres, with the result that the front tyres wear down more rapidly than those at the back.

Unless your car has unidirectional tyres (that is, those with treads designed to go in one direction only), a good way to do rotation is the cross or diagonal rotation method. This entails exchanging the front-right tyre with the rear-left one, and the front-left tyre with the rear-right one.

Vehicles with unidirectional tyres should only go for what is called straight rotation, which means swooping with the front-left tyre with the rear-left tyre and likewise for the right side.

Tyres should be rotated after every 5,000-8,000km travelled.

Air Pressure

Check your tyres regularly to ensure that they have the prescribed air pressure. Inadequate air pressure in tyres adversely affects driving stability, reduce fuel economy and may damage your car's suspension system. Over-inflated tyres, on the other hand, have less contact, which reduces their ability to absorb road shocks, and leads to a hard and bumpy ride.

Air pressure should be checked only when the tyres are cold. Tyres that have been driven for some time have built-up heat inside, and will give inflated readings. The optimum air pressure can be found in the vehicle manual or inside the car door.

Ideally, air pressure should be checked weekly.

Tyre Balancing

Tyre imbalance happens when there is uneven distribution of mass about the tyre's centre. Contrary to appearances, no tyre is completely symmetrical. Most will have "heavy spots" that cause imbalance in the wheel assembly. When your car moves, these heavy spots are pulled outwards by the centrifugal force generated by the movement of the wheels, which will then cause your vehicle to vibrate or your steering wheel to wobble.

Excessive vibration and instability of the steering wheel can be distracting, and a safety hazard, especially when you're driving over long distances.

Wheel Alignment

When you find your car continually pulling away from a straight path, veering slightly to one side, chances are that your wheels are out of alignment. Wheel alignment means adjusting the angles of the wheels, so that they are perpendicular to the ground and parallel to one another.

Wheel alignment should be done when fitting new tyres to your vehicle, and for every 10,000km thereafter.

Visual Inspection

Check tyre exteriors regularly for cuts, cracks, splits, uneven wear or bulges in the tread and sidewall areas. rims, valves, valve stems, valve caps and lug nuts should also be inspected. Remove any small stones or metal pieces stuck in the grooves.

If you notice a specific pattern of wear on the tyres, it may indicate a problem with the suspension. tyres should also be frequently examined for adequate tread depth: ensure that there is a minimum depth of 1.6mm.

Source: The Straits Times Saturday, November 13 2010