Avoid finding yourself flattened

New tyres are such expensive items that we have to get the longest possible service from them. Here's a list of dos and don'ts to achieve that.

l Check the tyre pressures regularly and do it when the tyres are stone cold. If one tyre suddenly starts losing pressure, the chances are that it has a slow leak. It's better to investigate this soon, rather than have a flat tyre at a bad time and place. Use your own gauge to check pressures - gauges at service stations are notoriously inaccurate. Use the pressure recommended by the manufacturer, not simply 200kPa because "that's what they all take".

l Don't underinflate your tyres. It leads to excessive flexing, which causes overheating, the biggest cause of sudden tyre failure. Never bleed air out of a hot tyre - a pressure build-up of about 20percent is normal on a long journey. A tyre underinflated by 20percent will lose up to 15percent of its tread life, but a tyre underinflated by 30percent will more than likely fail before it has completed 50percent of its life. Extended underinflated running will increase your car's fuel consumption by up to 10percent.

l Have the wheel alignment checked every 20000km, or whenever the first signs of uneven wear appear. Other symptoms include the steering pulling to one side or feeling loose or wandering, and excessive tyre squeal when turning. Be very selective about who you ask to check the alignment. It is a specialised job requiring knowledge, experience, expensive equipment and time.

l Act quickly to investigate any vibration on the steering. It might be a tyre that's out of balance. When having your tyres re-balanced, ask the workshop to check the balance before removing the existing balance weights. If the tyre is then in balance, or nearly so, your problem lies deeper.

l Use valve caps to prevent dirt getting into the valve core where it can cause sealing problems.

l Don't over-tighten wheel nuts, especially on alloy wheels. This can lead to cracking around the holes. It also makes it unnecessarily difficult to remove the nuts when the tyre must be taken off.

l Rotate tyres at regular intervals to prevent uneven wear, especially on the rear wheels of front-wheel-drive vehicles.

l Don't forget the spare tyre. The maximum life- span of a tyre is about six years from the date of manufacture, whether it is driven on or not. Beyond this point the compound deteriorates and the tyre could become unsafe.

l Fit new tyres to the rear when only two tyres are replaced. The considered opinion of the tyre industry is that this is the safest practice.

l Don't "buy down". From a safety point of view, and to comply with insurance requirements, high speed radial tyres - HR, VR, ZR - fitted as original equipment, must not be replaced with lower speed-rated tyres such as TR, even if you never drive at supersonic speeds.

l Finally, don't climb kerbs to park the car. I have been reliably told that this is one of the biggest causes of putting out the wheel alignment.