Tyres may seem simple but they are one of the most important and least understood components of your car.
Some simple rules apply to get the best from your tyres. Not the least important of these is that tyres require regular inspection and maintenance to ensure they provide the optimum safety and performance.
Thanks to recent developments in technology and materials, when looked after correctly, modern tyres offer longer life, and safer, more effective performance than we've come to expect in past generations.
So rule one is – don't take your rubber for granted.
We'll look at more tyre 'rules' in future advice articles but in the first instance let's set the record straight on a couple of things...
Myth: All tyres need to be replaced within five to six years
Tyre wear is determined by a range of factors including driving style, load, and environmental and storage conditions, so it is impossible to predict how long a tyre will last. However, even if your tyres show no visible signs of damage and the tread remains above the legal limit, most tyre manufacturers recommend replacing them every ten years as the rubber compounds and bonding in a tyre do slowly degrade over time.
In Australia, it is a legal requirement that all tread on a tyre must be a minimum of 1.5mm deep. All tyres are fitted with Tread Wear Indicators (TWI) and the location of these is usually marked by a symbol on the tyre sidewall. When any of the indicators are showing, the tyre must be replaced for the car to remain legally roadworthy.
Many modern tyres (especially those fitted to high-performance vehicles) have a unidirectional or asymmetrical tread pattern with the direction of travel indicated on the tyre sidewall. These should only be rotated front to rear on the same side of the vehicle.
Note some cars also feature different sized tyres and or wheels (sometimes called 'staggered') on the front and rear. If they use a symmetrical tread pattern, these can be rotated from side to side on the same axle. 'Staggered' asymmetric tyres cannot be rotated.
This should always be done when the tyres are cold and preferably with a good quality pressure gauge as the ones at the local service station are often not as accurate as they should be.
All vehicle manufacturers provide a minimum recommended tyre pressure for each model that is printed on a placard, usually inside the driver’s door jamb, and in the vehicle handbook. If your tyres are inflated to the recommended pressure, they will provide the optimum level of durability, safety, handling, comfort and fuel consumption.
Vehicle manufacturers set appropriate tyre pressure recommendations to ensure the maximum tyre life and effectiveness and these should be adhered to. You should only slightly increase tyre pressures to compensate for increased load or regular sustained high-speed driving.
At the same time, different types of rubber compounds used by different manufacturers will wear at different rates. Thus to ensure the longest tyre life and highest level of safety and performance, it is best to fit matched tyres (size, make and model) when it comes to replacement time.