You already know that driving on worn tyres is dangerous. In addition to drinking and driving or speeding, if you drive with unroadworthy tyres you’re also courting devastating, if not deadly, consequences.
In Australia, unroadworthy tyres cause thousands of accidents every year. In fact, a 2019 ACT study showed tyre failure was one of the most common causes of accidents, including tyre blow-outs from over-inflated tyres and worn tyres that take longer to brake, leading to rear-end accidents.
And, if a US study is anything to go by, more than a quarter of all road accidents could be caused by tyres with insufficient tread.
Apathy is also to blame.
Even though you know your tyres can mean the difference between braking in time, or holding to the road in bad conditions, the likelihood that you’ll do something to rectify tyre problems is slim, studies show.
A recent survey of 2,220 Australian drivers found 33% keep driving their car with unroadworthy tyres and nearly 50% put off buying new tyres for as long as they can.
When you think about it, that’s a lot of Australian drivers risking on-road vehicle failure by not replacing their tyre before they completely lose their tread or optimising their tyre pressure. And it begs the question, how safe are you really on the road?
All about the tread.
Protecting yourself and your family on the road begins with understanding how treads work and when it’s time to get new tyres.
Put simply, bald tyres are an accident waiting to happen, particularly on wet, icy and treacherous roads. And driving on worn out tyres in snow is one of the most dangerous challenges you’ll ever face as a driver. But do you know why?
If you’ve ever looked closely at the surface of your tyre treads, you’ll know they have a range of grooves or channels across their surface. The pattern changes depending on what tyre you purchase and they’re not there by accident.
Tyre treads are designed to create the maximum traction between your car and the road. When they’re new, they’ll grip the road reliably regardless of the weather conditions. The tread effectively forces water away from the tyre, allowing it to maintain a solid grip on the asphalt and helping you steer the car in the right direction.
But once they begin to wear down, they can’t force the water away and your ability to control your car on wet, slick or icy roads will begin to deteriorate.
Driving also creates friction between your tyres and the road’s surface. Treads let the heat built up by this friction dissipate by allowing air to flow between the grooves. When your tyres are bald, this heat can’t escape and your risk of on-road, at-speed blow-outs increases.
What’s the optimum tread thickness?
A new, roadworthy tyre’s tread should be between eight to twelve millimetres thick, contingent on what size they are. If they’re less than 1.5 millimetres thick, your car is unroadworthy and you should replace your tyres—stat.