NAPA AUTOPRO

Winter tires vs. 4-season vs. all-season tires

All-season tires sound like they’re truly meant for all four seasons, don’t they? In fact, they’re only designed for spring, summer, and fall. Winter tires perform best in the sub-zero temperatures of winter, and 4-season tires can be used all year round, depending on where you live.

In this blog post, we’ll discuss the differences between these tires, then explain when you may need to switch tires and how best to do it.

First things first: your local law

Québec has legislated winter tires for the entire province. B.C., on the other hand, has localized laws for winter tires and chains. Ontario is one of many provinces that does not legislate winter tires, but it has laws regarding when and where studded tires can be used.

Before considering whether to switch tires, make sure you know what your local laws require drivers to do. If you plan on using 4-season tires, check that they’re approved in jurisdictions that require winter tires.

Check the temperature

Each type of tire performs best in a specific temperature range. As the seasons change, 7 ˚C is the temperature to watch if you alternate between winter and all-season tires.

When fall weather consistently cools down to this temperature, it’s time to switch to winter tires. When spring temperatures rise to 7 ˚C, you should change back to your all-seasons. Transport Canada and the Tire and Rubber Association of Canada (TRAC) recommend this temperature.

If you use 4-season tires, check the manufacturer’s limitations: although these tires are manufactured for moderate winter conditions, they will not have the grip and stability you want for very cold winters.

What’s the difference between all these tires?

When it comes right down to it, tires differ in the materials they’re made from, because these materials behave differently depending on the weather. All-season, 4-season, and winter tires also have different tread designs.

How does the temperature affect your tire selection? Remember that winter tires are manufactured for temperatures of 7 ˚C and lower, whereas all-seasons perform best above 7 ˚C.

The average winter low in Vancouver is 1.4 ˚C, and the average summer high is 22.2 ˚C. The average temperature in Québec City, though, ranges from a low of -17.7 ˚C in the winter to a high of 25.0 ˚C in the summer. Churchill, Manitoba, reaches an average winter low of -30 ˚C and an average summer high of only 18 ˚C.

Avoid using winter tires in the warmer weather in all three locations, because the temperatures will cause winter tires to become too soft. This means they’ll offer less grip and will wear down faster. The average low for Churchill and Québec City will also likely be too cold for 4-season tires.

Among these three cities, Vancouver is the only location where drivers might consider using 4-season tires. However, remember that British Columbia requires winter tires or even winter chains on some highways and roads during the winter. Double-check requirements before travelling.

Treads on all three types of tires also differ. Whereas all-season tires are shallower and designed to push water and mud out of the way, winter tires have narrower but deeper grooves to push all kinds of precipitation out of the way while also providing grip on ice. The treads on 4-season tires fall somewhere in between.

Are your winter tires actually approved for winter?

Transport Canada uses different symbols to show consumers what conditions their tires have been tested and approved for:

  • A three-peak mountain with a snowflake indicates that the tire has been approved for severe winter driving conditions. This symbol is also found on 4-season tires.
  • A maple leaf means Transport Canada has approved this tire for use in Canada. It does not mean the tire has been approved specifically for winter driving.
  • “M+S” without the mountain means the tire has been manufactured for mud and snow, but not for extreme weather. You’ll find this designation on all-season tires.

While all-season and 4-season tires might sound like cheaper alternatives to the semi-annual tire change, you increase your risk of an accident, may spend more on gas because of the decreased fuel efficiency, and may miss out on seasonal insurance savings.

Maintaining your tires

Regardless of which tires you have on your vehicle, maintaining them properly can increase their longevity and improve overall driving safety.

  1. Make sure that all the tires in a set are of the same kind and are changed at the same time. Don’t mix all-seasons with winter tires or change just the worn-out tires in an effort to save money. You’ll pay in the form of reduced stability on the road.
  2. Inspect tire wear and pressure monthly. Winter tires with a tread depth under 4 mm (5/32”) increase your risk of sliding or hydroplaning. Buy new tires instead.
  3. Review recommended air pressure values for your vehicle. Better air pressure in your tires will not only improve safety, but increase fuel efficiency as well.

Are winter tires really necessary?

If you live in an area with regular snowfalls and icy conditions, yes, winter tires are necessary. Researchers from Québec’s ministère des Transports et de la Mobilité durable (Department of Transportation and Sustainable Mobility) compared collision data for the 2008-2009 and 2009-2010 winter seasons with data collected before all cars were required to have winter tires. They found the following:

  • a 5% decrease in road collisions;
  • a total of 574 fewer people had been injured in a collision;
  • a 3% reduction in deaths and serious injuries.

Furthermore, the Tire and Rubber Association of Canada reports that winter tires offer up to 50% better traction in winter than all-season tires.

To schedule your winter tire change, contact your local NAPA AUTOPRO service centre.

For additional information, view these articles below:

Does It Matter What the Groundhog Says? – NAPA AUTOPRO

Winter Tires: When Should You Make the Seasonal Switch? – NAPA AUTOPRO

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