Why Drivers Shouldn’t Use Winter Tires in Summer
There’s nothing like driving a set of responsive winter tires when conditions turn cold and dangerous. Indeed, in many parts of North America it’s vital to rely on a set of winter or all-weather tires, whose softer compounds safeguard drivers in snow, ice and cold.
But once the snow and ice melt and summer heat sets in, those same tires can be major liabilities. The very compounds crafted to make tires safe in winter conditions aren’t built to withstand heat or consistently wet roads. Simply put, winter tires do not have the necessary characteristics for safe summer driving, even if they have sufficient tread depth.
”We design our winter tires to be reliable in snow and ice,” says Steve Bourassa, Nokian Tyres North America’s director of products and pricing. “But winter strength becomes summer weakness, and it’s important that drivers consider all-season or all-weather tires once temperatures warm.”
Wet asphalt is challenging for winter tires
Several tests have determined that winter tires perform poorly in the summer. The differences are especially clear in summer rain.
A recent summer tire test from Finnish automotive magazine Tekniikan Maailma shows that when a worn non-studded tire is used to brake from a speed of about 50 miles per hour, the car will still be going 25 mph by the time a new summer tire would have stopped. Braking grip on dry asphalt is also clearly poorer than with summer tires.
The test also reveals that controlled driving on wet asphalt is nearly impossible with worn winter tires, since sliding starts without warning and restoring control of the vehicle is challenging.
In summer, winter tires steer slowly and feel unstable to drive
The heavy block pattern and densely siped tread make winter tires steer more slowly than summer tires. When a tire steers slowly, it will not be as precise when it faces surprising conditions.
“If you assume during a sudden evasion that winter tires will steer as quickly as summer tires, you may end up crashing or veering off the road,” Bourassa says.
Non-studded winter tires or tires with studs removed are also less stable than their all-season or all-weather counterparts. The winter tread compound combined with a block pattern is no match for summer tires in terms of rigidity.
“On a hot summer day, you will need to make steering corrections with winter tires even when driving straight,” says Bourassa, “since the tire will have more lateral flexibility than all-season tires, which are more rigid.”
Tires wear down quickly in warm weather
Winter tires have soft tread compounds designed for winter use; in hot summer weather, they will generate an unnecessarily high amount of heat and increase the overall thermal load of the winter tire.
“When the tread is too warm, this will transfer to the tire structure,” says Bourassa. “This results in durability problems. In the worst case, the tire components may break apart, causing the structure to fail. This will cause the tire to break.”
Winter tires also wear out more quickly in warm summer weather, which may create an abnormal serrated pattern on the tread. Serrated tread causes noise and vibration. In addition to an unpleasant driving experience, this may result in problems with the car, as continuous vibration is not beneficial to the suspension or bearings.
In addition to accelerated wear, the tire may also break if rocks collect in the empty stud holes of a tire with the studs removed. The rocks may pass through to the steel belt package inside the tire and break it.
All-weather tires provide a solution
While winter tires are far from ideal on warm, wet summer roads, Nokian Tyres’ all-weather products are built to withstand conditions on both ends of the calendar. The Scandinavian company invented the all-weather tire in response to consumers who wanted a winter-rated product they could use year-round.
All-weather tires are marked with the Severe Service Emblem (also known as the Three-Peak Mountain Snowflake) that certifies they are appropriate for winter use. They are also effective on spring and summer roads, making them a good choice for drivers who don’t want to switch tires twice each year.
Characteristics of a good all-season or all-weather tire:
Low rolling resistance
Good wet grip
Good aquaplaning resistance
Good driving stability