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Winter Tires are designed to deliver safety and control in snow, ice, and cold weather conditions. Many people think that all-season
tires can deliver this same performance, but this is not true. The superior traction that winter tires
deliver, as much as 25 to 50 percent increase over all-season tires, can very well be the margin you need to stop
in time or to turn and avoid trouble. The Rubber Manufacturers Association has gone so far as to set a new
standard for winter traction, so read on and know the difference:
Winter tires have special tread compounds that use one or more of the following features to deliver improved
traction:
- "Soft stud" tread fibers "bite" like metal studs yet are quiet and do not harm the road.
- Special compounds retain their flexibility even in the coldest temperatures. A more flexible tread surface
equals more traction and control.
- Silica-based, micro pore compounds (or comparable technology) are used to bite through the water film and
increase snow and ice traction.
All-season tires have very different compounds:
- Compounds are "averaged" to deliver better wear and good traction in a wide range of conditions, but the trade-off is a decrease in traction below 45 degrees Fahrenheit. This is the point where all-season tire compounds begin to harden and lose traction.
- These tires must use denser compounds to deliver better wear. Micro pore or comparable technology is not suitable for these designs.
- For the same reason no soft stud material is built into these tires.
Winter tires have tread designs dedicated to improving snow and ice traction. Today's most advanced winter designs
deliver this while maintaining a comfortable, quiet highway ride as well as excellent dry traction.
- Wider circumferential grooves enhance winter traction by providing efficient channels to drain water and expel snow.
- Unlike snow tires of old, smaller shoulder grooves increase snow and ice traction with no sacrifice in dry handling or highway ride.
- Special lug and groove shapes allow more snow to be packed into the tread and expelled as the tire rotates for better deep snow traction.
- Sophisticated, high-density sipe designs (sipes are the little slits in the tread surface) help cut through water and slush so the tread compound can make better contact with the road.
- Rounder casing designs add traction by cutting into the snow's surface.
All-season type tires can not include these features and still deliver the wear and high temperature traction that
is required for driving during other times of the year.
- Shoulder blocks and groove designs are a "compromise" that must meet cornering, wear and all-season traction
requirements.
- Less aggressive tread designs deliver more highway ride comfort, but tend to pack and not expel snow as
effectively as winter tires.
- Less siping is used.
- Flatter tread designs enhance dry traction but don't cut into snow effectively.
To help you select a winter tire that improves your margin of safety, the RMA (Rubber Manufacturers Association)
designates winter tires that meet the new severe snow standard with a new symbol. This sets them apart from
standard M&S rated all-season designs.
Remember that four winter tires are recommended to achieve optimum traction and safety. |
