Research shows that when driving with worn tires, aquaplaning can begin at speeds that are clearly slower than normal road speeds. Nokian Tires recommend that drivers should monitor the condition and inflation pressures of their tires regularly and not only during the tire changing season. Safe summer tires should have a minimum tread depth of four millimetres and they should be no more than six years old.
“Poor tires are among the major traffic safety risks in summer traffic. The grip on worn tires will collapse in wet weather, which will jeopardise safety especially under extreme conditions,” says Matti Morri, Technical Customer Service Manager for Nokian Tires.
“The test tires that were determined to be dangerous were nevertheless completely legal, that is, they had a tread depth above 1.6 mm. The driver has full responsibility for monitoring tyre wear. In addition to tread depth, you should also check the tre for cracks and regularly verify that the inflation pressure is correct. As the tyre gets older, its characteristics will also weaken, so you should bear in mind that the maximum service life is six seasons. For the family’s second car and other cars that are used less often, you should ensure that the overall age of the tyre is less than 10 years. This is easy to check on the tyre sidewall where you can find the tire’s year of manufacture,” Morri says.
Maximize service life by rotating tires from the front to rear
In order to maximise safety and save money, you should ensure that the tyre does not wear down abnormally. A tyre that only wears down on the inner or outer shoulder is a symptom of something being wrong. It is often a sign of excessively low inflation pressure, incorrect alignment or worn shock absorbers.
“Abnormal wear will have a direct impact on handling. Unless you act on time, the wear may even reach the tyre body and destroy it completely. For example, you should remember to check your tyre pressure once every three weeks. When setting off on longer trips or transporting heavy loads, you should increase the tyre pressure in proportion to the load,” Morri says.
Many drivers wonder why two tyres in a set are often much more worn than the other pair. According to Morri, the driving tyres will always wear out twice as quickly as the free-rolling tyres. Therefore, you should rotate your tyres from front to back every 8,000 kilometres or whenever the difference between the front and rear tread depth is more than 2 mm.
‘By rotating their tyres, drivers can maximise their service life, the safety of themselves and others on the road as well as save money. Rotating greatly extends the life cycle of the tyre set. Tyre wear is also greatly affected by the vehicle in question and the driver’s driving style and activity. You can save money by choosing high-quality tyres that suit your vehicle and driving habits,” Morri says in closing.
Are your summer tyres in order? Track the following as the season progresses:
- Check the tread depth. The minimum safe tread depth is 4 millimetres; any less than that and the risk of aquaplaning will increase substantially. Summer tires from Nokian Tires make it easy to monitor tread depth with the patented Driving Safety Indicator (DSI) that displays the remaining tread depth in numbers.
- Check the sidewalls and tread of the tires. You should check the surfaces visually for cracks, splits, punctures or abnormal bulges, since they may affect the durability of the tire.
- Check the main grooves. Any large rocks that are stuck in the main grooves will penetrate deeper into the tire while driving and may cause tire damage. You can use a screwdriver to remove the rocks, for example.
- Check the wear pattern on your tires. Tires that are worn unevenly or abnormally quickly may be a symptom of problems with the car’s wheel alignment. In addition to safety, abnormally worn tires will also affect driving comfort, so you should have the car’s alignment checked.
- Check that all tires are evenly worn. You should rotate the tires in order to make them wear down as evenly as possible. This will improve the car’s handling. Generally speaking, the tires on the driving wheels will wear out quicker than free-rolling tires. If the tires are evenly worn, you should rotate them from the front axle to the rear approximately every 8,000 kilometres. If two tires are much better than the others, you should fit them on the rear axle for safety reasons.
- Check the age of your tires. The service life recommendation for actively used tyres is 6 years and the maximum recommendation for the total service life is 10 years. The tire’s sidewall has a four-digit manufacturing time code, where the first two digits indicate the manufacturing week and the latter two indicate the year. If the code is 1717, for example, then the tire was manufactured in week 17 of 2017.
- Check the inflation pressures of your tires. You should check the tire pressures every three weeks, since correctly inflated tires will improve the car’s handling and reduce braking distance. Underinflating tires will also be more costly, since driving with underinflated tires will put an additional burden on the tire’s structure and result in substantially higher fuel consumption. See our video for tips on checking inflation pressure.