Don’t call them snow tires. If you live where fall colors give way to snow and ice-covered roads, buying a set of winter tires may be a prudent decision.
We recently put Michelin’s latest and greatest X-Ice Xi3 winter rubber to the test in a controlled setting—the hockey rink at the University of Notre Dame, not far from retailer Tire Rack’s corporate headquarters. Although we never got above 15 mph, we were reminded of how effective dedicated winter tires are on a slippery, cold surface.
Think of tires as you would your shoes. If it’s a snowy day, would you put on a pair of slick-bottomed dress shoes or high heels? Not unless you wanted to end up doing snow angels at the bottom of your driveway.
Need quantifiable evidence? In Quebec, winter tires were made mandatory about a decade ago. In just a few years, the Quebec Ministry of Transport found a 17 percent drop in winter crashes and a hefty 36 percent decline in deaths or serious injuries attributable to snowy weather car crashes.
Few places in North America aside from some mountain passes in the Western U.S. and some parts of Canada have made winter tires mandatory, but laws here are beginning to catch up with those in most of northern Europe where they’re required. That doesn’t necessarily mean that you need to wait for legislation.
What makes winter tires different?
Winter tires have largely supplanted dedicated snow tires for most manufacturers. The difference here is that winter rubber consists not only of tread designed to bite into snow and ice, but also a specific rubber compound that’s vastly different from the all-season or summer tires your car was delivered with.
Obvious at first glance is the siping integrated into the tire’s tread. Sure, it’s possible to have a tire shop cut sipes—thin lines—into non-winter tread blocks, but that’s kind of like trying to shove a dress shoe into a hunting wader. It works, but not really.
Siping is designed to both wick away moisture and to adhere to a slippery surface. Newer siping technology employed by several big tire manufacturers helps the tires last longer while improving grip.
What’s not as noticeable is the rubber compound itself, which takes advantage of silica-infusion technology to make for a far stickier surface on cold surfaces both dry and frozen. Summer tires—the kinds you’ll find on most sports cars—are exceptionally ill-suited to cold roads for the same reason that they stick like glue on a warm day. The rubber compound used on summer tires becomes rock-hard and smooth as glass below about 45 degrees, making sports cars downright dangerous—if not entirely undriveable. All-season tires are better, but Tire Rack’s Woody Rogers calls them a “jack of all trades and master of none,” noting that they’re perfectly fine for quiet three-season highway cruising but come up short as temperatures drop due to both the rubber employed and especially to their tread.