All-season tires are not All-weather tires

confusion reigns

There is a big difference between all-season and all-weather tires.

There’s a new tire in town — the all-weather tire. Not all-season, all-weather. The difference in name, does not fully reflect the difference in performance and safety.

All-season are a compromise. They are the jack-of-all-trades and master of none. Good, but not great for spring, summer and fall use. Not good for winter. The issue is the ambient or outside temperature. All-season tires are designed to remain effective at temperatures ranging from seven to 30 degrees C. As you exceed either end of that scale, they become too hard or too soft. Below seven degrees, they become hard and lose their effectiveness. Above 30 they become very supple and wear incredibly quickly.

For this reason, pure winter tires hugely out-perform all-season tires during the cold months. Similarly pure summer tires are much better in hot summer conditions.

click here to learn why you need four tires 

Tests prove effectiveness

During numerous tests in North America and Europe, I have driven or witnessed vehicles on a set of all-weather tires come to a stop in 20 per cent less distance than on high quality all-season tires. Pure winter tires cut an additional 15 per cent from the distance.

Obviously, if all-season tires are not effective in cold weather — wet or dry, they will be less so when the surface is slippery.

Winter tires have a tread designed to cut through and dispel snow or slush. Their compound is designed for cold conditions, and they carry the all-important three-peak mountain snowflake (3PMSF) symbol. This tells us they pass rigid tests for cold operations.

Lots of science & chemistry involved

A huge amount of science and chemistry differentiates all-weather from all-season tires. The only visual difference is that small 3PMSF pictogram.

Tires that have been tested and approved for winter use wear the “mountain/snowflake symbol

This test tells more than the vague M+S marking, which refers to tread design, not the compound beneath. M & S (mud & snow) on the sidewall is meaningless, there are no tests to pass and manufacturers can, and do, put them on any tire they like.

Click here to learn about minus sizing 

A Great compromise

All-weather tires are a great compromise for Canadian conditions, and for those who travel south for the winter months. They eliminate the need for two sets of wheels and tires, and the added costs associated with storage and swapping twice a year.

For this reason all-weather tires got their beginning and are most popular in northern Europe where winter tires are compulsory. All weather tires have also become prominent in Quebec, where the same rules apply.

Most major companies now offer all-weather tires 

Most major tire companies now offer all-weather tires, including B F Goodrich, General, Goodyear, Hankook, Kumho, Michelin, Nokian, Toyo, Yokohama and Vredestein. 

If you store your vehicle for the winter, all-season tires will suffice, or if you go south for the winter, live in an urban area where snow is cleared on a regular basis, or can park your vehicle during a winter storm, all-weather tires might be the answer.

If you “must” drive, regardless of conditions, get a set of high-quality winter tires.

About Richard 166 Articles
At the age of five I was already obsessed with all things automotive being able to identify the make and model of car by just the sound of its engine going down the street in front of our house in the small town on the south shore of Nova Scotia. Although I have been covering and writing about the automotive scene for more than 40 years and the light still grows brightly.