How to Choose Snow Radial Tires
Most all-season tires on the road today are radial tires. Many snow tires are also radial tires. In radial tires, the reinforcing cords lie across the tires at 90 degrees to the direction of tires. This is different from bias ply tires, where the reinforcing cords are at the crown angle of 45 degrees in the sidewall region and 60 degrees at the bead. This reduces the rolling friction of radial tires, but it also reduces the ability of a radial snow tire to channel snow and slush away from the footprint.
When choosing a radial snow tire, the first thing to look for is the symbol of amountain with a snowflake on it. It will usually be located to the right of all the other specs. This symbol indicates that the tire has passed the snow test for traction. Ignore other ratings such as mud and snow (M+S, M/S, or M&S), Alaska, Arctic, A/T or AT Blizzard, Ice, LT, Nordic, Snow, Ultratraction, or Winter. These don't require any tests at all. Without the snowflake/mountain symbol, a radial tire is not a true snow tire.
However, even the mountain/snowflake symbol doesn't mean it's a real snow tire. There is no ice test, so the mountain/snowflake won't tell buyers how the tire performs on ice.
For this, look for a deep open tread. Heavy-duty radial snow tires have transverse zigzag grooves extending across the entire tread, with deep longitudinal linear grooves connecting them. These deep grooves shed snow and icy water, so that the tire is constantly getting rid of slush buildup and is able to bite into snow and ice. Drivers will need that grip on the road surface during winter driving.
Another thing to look for is the type of rubber compound used in the tire. Radial snow tires should be made of AA or A grade rubber, the softest available. These softer rubber compounds stay flexible and don't get brittle in cold weather. Rubber compounds which are graded B or C lose traction in cold weather and start to get brittle in temperatures as warm as 7 degrees Celsius.
When choosing radial snow tires, also make sure the tire meets the specs set out in the owner's manual. Tires that are too big or too small for the vehicle will rub against the fender walls and suspension, greatly shortening their life expectancy.
Always put radial snow tires on all four wheels. Mixing radial tires with standard tires is dangerous. On the steering wheels, radial snow tires will help the car to go the direction the driver wants it to. On the drive wheels, radial snow tires will get the car going and help it to stop. Even if the car normally has radial tires, putting radial snow tires only on the drive wheels is a sure recipe for askid.
Make this winter an accident-free winter. Choose the right radial snow tires, drive safely, and never lose grip on the road again.
