If you were to look at tire track markings left in dirt, the distinctive patterns may remind you of a shoe print. And, just like comparing the prints left by winter boots and summer shoes, you can work out which are snow tires, and which are summer tires. Along with other tire features, the unique patterns designed for winter tires influence your vehicle’s traction, grip and brake performance – especially on ice, wet surfaces and in snow. In this article we’ll investigate why tire patterns are so distinct and why tread is especially important for winter tires.
In harsh winter conditions, a tire’s tread pattern enhances a vehicle’s grip and handling on icy roads. It is formed from four main divisions:
While these four main divisions help form a tire’s pattern, there’s a fifth element that makes all the difference for winter tires – the tire compound. Winter and all-season tires are made from a specially formulated natural rubber compound that is softer and more flexible than summer tires. It means, they’re able to offer much better grip and traction in lower temperatures. The winter tire tread design offers its benefits especially on roads covered with snow or mud. The snow gets pressed into the wider and deeper tread grooves and by this it utilizes the effect of shear forces on snow for additional grip. The wider grooves can also absorb more slush contrary to summer tires and ensure more contact to the road surface.
You can learn more about the differences between summer and winter tires here. Overall, these 5 elements work together by interlocking and biting into snow and ice to provide additional traction and improved braking.
As mentioned above, winter tire patterns have larger, deeper grooves and additional thin channels known as sipes. This combination allows greater brake control, traction and safety when driving in snow or icy and muddy road surfaces. Additionally, when snow gets compacted into the deep grooves, this helps create further traction.
The performance of an all-season or winter tire depends largely on the tread depth. As tire tread wears down over time, its ability to maintain grip on frosted roads reduces. To ensure optimum driving performance and more importantly driving safety, your tires should always have sufficient tread. Always consider the legal regulations of your country and take into account that tire performance decreases with tread depth, especially in winter conditions.
You should aim to check you tire tread depth at least every two weeks, along with your tire pressure. You can do this is two different ways:
Use a tread depth gauge, inserting the probe into the groove and pushing the shoulders down to the surface of the tire. Do this across several sections of the tire and ensure the tread depth meets the legal requirements in the country you are driving in. If it's below this measurement, it's time for new winter tires. In a pinch, you can also use a coin to check your tread.
Check your tread wear indicators, sometimes referred to as wear bars. All tires are manufactured with a series of small rubber bars embedded in a section of the tire grooves. Once the tread is worn down, these bars are flush with the level of the tread pattern. This means the tire has reached its limit of winter suitability and it is now time for new tires. Note: you may need to rotate your tire a few times to find the wear bars.
When checking your winter tire tread, look for any damage such as unusual bulges, small scoops and divots in the tire. They could indicate that your tires are misaligned or that there may be other problems with your vehicle. If you do find any damage, visit your local tire specialist as soon as possible for a thorough check. You should also closely check the conditions of your winter tires when you prepare your vehicle for the cold season.