Winter Tires vs. All-Season Tires
- Winter tires can provide enhanced braking performance in snowy & icy conditions
- These tires perform well in all types of winter conditions – snow, ice, sleet, slush, wet and even cold dry roads
- Winter tires feature tread designs made specifically for ice, snow and other severe winter conditions
- They have specially formulated tread rubber that stays flexible at low temperatures for better vehicle control
- The aggressive tread on a winter tire reduces snow build up
- Most drivers find that winter tires provide a sense of confidence and control in challenging winter weather conditions
- All-season tires are designed to help provide traction and grip in wet and snowy conditions
- They are made to help provide stable handling and even treadwear in both wet and dry conditions
- Although all-season tires offer traction in a variety of different weather conditions, winter tires surpass them when it comes to traction in snow and ice
According to Edmunds.com:
Snow is just one challenge among many, so forget the term "snow tires." A more accurate term is "winter tires," as they're designed to improve acceleration, braking and handling across the whole range of cold-weather conditions.
Of course, such challenges have been overcome to some extent by the sophisticated safety equipment that's now standard on so many vehicles. It's easy to be lulled into a sense of near-invincibility by ABS, VSC and a slew of other engineering wonders whose three-letter-acronyms (TLAs) have become part of our everyday language.
But this technology is ultimately dependent upon the physics that takes place at four fist-size contact patches — literally, where the rubber meets the road. Vigilance upstream can only do so much to make up for bad behavior here. (AWD, by the way, will help you accelerate in the snow, but do little for your stopping and steering. And on ice, it's really all about the tires.)
The engineering involved in developing winter tires is, as one might guess, remarkably complex. Still, it more or less comes down to three factors: tread design, tread depth and the rubber compound.
Winter tires use siping, a series of slits in the tread blocks, to increase the number of edges in the tire's contact patch. As the tread blocks flex, each edge bites into the snow and ice. Greater tread depth allows for flexing and helps channel snow and slush across the tire's surface, away from the contact patch.
The type of rubber itself is also important. Winter tires are built using rubber compounds that remain soft even in extremely low temperatures. On the other hand, most summer and all-season tires use rubber compounds that harden at low temperatures, resulting in compromised cold-weather performance.
"The hardness of these tires at lower temperatures means they no longer conform to the surface of the road," says Joerg Burfien, director of research and development for Continental Tire. "This leads directly to reduced grip on the road and a much-reduced overall performance — mileage, braking distances, cornering, handling, etc. — ranging from 20-25 percent."