The importance of tread on winter tires

November 27, 2020

Most of us know that having high-quality all-weather tires or switching your summer tires for winter ones in the fall is a necessity of life for Canadian winter, but few people think past making sure it gets done. There are some facts you should know about the tread on your tires to help you decide when they should be replaced.

Why is tread important?

The tread on the tires grips the road when you are driving. When your tires start to get worn down, it becomes harder to control your vehicle, the traction is not as good and your braking time gets worse. Make sure to check your tire tread depth as part of maintaining your car.

What is special about the tread on winter tires?

Winter tires are worth buying because they are created specifically for cold, snowy, icy and wet conditions. Their tread depth is deeper than that of all-season tires. They are made for low temperatures and they perform better in winter. Winter tires have a tread pattern that is single-directional and pushes ice and snow away.

What is a typical tread depth?

New winter tires have a tread depth of around 10/32 to 11/32 inches. Tires that have been used but still have life in them, have about half the tread depth of new tires, about 5/32-6/32 inches.

At what tread depth are winter tires worn out?

Your winter tires are unsafe and need to be replaced when the tread depth is 2/32 inches, but even tires with more tread left on them will perform worse than new tires. You may want to consider replacing your winter tires well before they get to 2/32 inches. For winter driving, a tread depth of at least 5/32 inches is recommended because winter conditions require thicker tread.

What happens when your tires start to wear down?

According to Consumer Reports, when all-season tires lose half of their tread the following issues start occurring:

A slight loss in braking effectiveness.
Hydroplaning resistance goes down by 8 per cent.
Snow traction declines by 14.5 per cent.
Wet braking ability decreases by 6.8 per cent.

What are tread wear indicators?

Wear bars, or tread wear indicators, are evenly spread out in the main grooves of the tread. Some winter tires have winter tire wear indicators that tell you when the tires are no longer suitable for winter driving.

How to check the tread depth on your winter tires

Go to an auto parts store and get a tire tread depth gauge. Measure the depth of the tread by inserting the probe bar in the tread groove, pushing the shoulders so they are level with the tread.
Judge the wear of the tires by the smallest tread depth you can find. If any grooves are at 2/32 inches, it is definitely time for new tires but you should consider replacing them at 5/32 inches.
Or check the tread wear indicators in the main tire tread grooves. If they are level with the tread you need to replace your tires.
Also, make sure to check for other damage to your tires. Small divets in the tread can mean misalignment or other issues. Bulges in the tread or sidewall are also bad news and if you find one you need to replace the tire.