With winter in full swing in some parts of the country, it’s a great time for a primer (or a reminder, if you’re already in the know like most of our gearhead readers) on the different ratings and acronyms found hammered into the sidewalls of modern winter tires.
Before diving into that particular patch of weeds, it’s worth reiterating the importance of winter tires and the grip they offer when the weather turns foul. First of all, you’ll notice we are calling these things winter tires and not snow tires, a distinction present in the modern age since top tier winter rubber from established companies like Nokian or up-and-comers like Sailun add large doses of tractive properties when the ambient air temperature simply drops below 45 degrees Fahrenheit.
Promoted Product: Sailun Ice Blazer WSTX
When it comes to winter driving, you want a tire that is 3 Peak Mountain SnowFlake (3PMSF) rated. These tires are made with a special rubber compound that is pliable in cold weather (at or below 40º F), giving the tire better grip on snow and ice-covered roads. The difference is in the conditions. For winter, a 3PMSF tire will outperform other tires. That is why a tire like the SAILUN Ice Blazer WSTX is a superior option for your vehicle. The tread is heavily siped with directional tread and the compound of the rubber is highly flexible. You can even add studs for better traction still. The key thing is, these tires are meant for winter conditions only. When the snow flies, these tires are the best way to give your vehicle the best traction possible.
Sailun USA – https://gosailun.com/en-us/plt/tires/wstx/
Sailun Canada – https://sailuntire.ca/en/plt/tires/wstx/
Thank the molecular properties cooked up and baked into the rubber by brands like the ones mentioned above. This is a closely guarded secret mixture that can be silica- based and which, in winter tires, permit the rubber to stay flexible in cold temperatures, explaining why a Cup 2 R tire will send you skidding into a snowbank despite its phenomenal summertime grip. This chemical concoction is aided by smart tread design which, for grip purposes in winter conditions, packs saw-toothed sipes into effective blocks which are placed strategically to offer both linear and lateral grip.
Most drivers in the snow belt are familiar with the three-peak mountain snowflake icon, abbreviated to 3PMSF and denoting tires which have passed a certain measured threshold for performance standards in winter conditions. About 30 years ago, the U.S. Tire Manufacturers Association created a standard for winter tires, one which used measurements and maths to evaluate a tire in snow. Comparing that data to a baseline set down by a standard tire, the 3PMSF designation focuses on traction expectations.
However, it is worth noting it only considers traction minimums in a specific set of circumstances – not during turning or braking, for example, nor does it measure stoutness on icy roads. The latter is worth mentioning since many areas in this country may find themselves coated in a February sheet of ice more often than buried under a foot of snow. In other words, it is still a good idea to do one’s research and not just blindly select a tire simply because it has the 3PMSF designation. With tire technology advancing by leaps and bounds, more tires are able to clear the standard for three-peak designation than ever before. Will the industry create a next-level winter tire label – say, a four-peak mountain snowflake? We actually put this question directly to some industry execs earlier this year, folks who grinned at the notion but were quick to agree the three-peak bar is arguably easier to clear these days before pointing out it’s not like the threshold has been lowered. Reading between the lines, we think there are similar conversations being held in stuffy boardrooms at tire companies around the globe.
But what about the so-called ‘mud and snow’ designation which crops up on the type of tire which is often marketed to truck and SUV owners? Surely, if the word ‘snow’ is part of the designation, it means the tire should be able to handle winter’s worst, right? Well, not exactly.
Throwing all the way back to the 1970s, shoppers began finding the ‘M+S’ designation on some of their favourite tires, or some variant thereof (M&S, M/S, and the like also appeared depending on brand). This was very much a self-policing label, since there was (and is) no official test to pass when making an M+S claim. Think of it more as a marketing exercise onto which just about every tire manufacturer latches, a phrase which sounded tough and pointed the way to tires with a tread pattern which was knobbier than one generally found tires hove under the family station wagon.
These tires often do have wide grooves between the tread blocks to help prevent mud and snow from scuppering traction by packing into its footprint area. Since there are notably fewer sipes (defined above) in the tread pattern, these tires don’t perform as well on ice as ones with the 3PMSF badge of honor. These days, M+S is generally understood to be part and parcel of an all-season tire which can serve duty in the dry but not completely fall apart in terms of traction when the road gets a bit muddy or is covered in a dusting of snow.
Choosing the right tire for winter weather can make the difference between making it to work and dealing with an auto repair facility. Knowing these definitions can help ya make better, and safer, buying decisions.
[Main image: Alones/Shutterstock.com. Product image: Manufacturer]
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