Tires and ice: Winter driving challenges

Early winter storms and temperatures that have bounced from sub-freezing to above normal have alerted us to some of the challenges of winter driving. This week in the New York area the sun was brilliant and it was mild enough to walk outside without a coat. Last week the thermometer was down in the low teens. That 50-degree Fahrenheit difference doesn’t just pose a wardrobe dilemma, it may be the reason your car ends up in a ditch instead of staying safely on the road.

Because there’s nothing tempting about checking your tire pressure when the cold is biting and the pavement icy, you may have put it off for months. Bad idea. Tires lose about one pound per square inch (psi) of pressure for every 10 degrees Fahrenheit the temperature drops. (And the reverse is true when the mercury rises.) So the change in temperature from last week to this may mean your tires could be under inflated by five psi—more if they weren’t properly inflated properly to begin with.

Tires that aren’t inflated to the right pressure can lower fuel economy, wear out faster, and handle sluggishly. Worst of all, they may fail. So don’t take it for granted that your tires are safe; check them with an accurate gauge and inflate them to the pressure listed on your car door placard, in the owner’s manual, or in the glove box. (The number on the sidewall of the tire is the maximum to which it should be inflated; stick with the automaker’s recommendation for your particular car.) Our experts advise checking tires at least monthly when temperatures are typical of the season, and again after a big rise or drop. Take the pressure when the tires have been sitting for at least three hours, since tires that have just been driven will have a slightly elevated pressure.

If you drive a car with performance summer tires, you may also find that the cold weather has made them more like wagon wheels. Summer tires that grip just fine when it’s, well, summer, are not meant for freezing weather. In cold conditions, they can become stiff and lose their grip on the road, even when snow and ice aren’t a factor. Switch to all-season or winter tires and save the summer tires for warm weather.

Ice follies
After snow storms earlier this winter led to a flurry of accidents on Connecticut roads, the state announced it would start ticketing drivers who failed to clear the snow and ice from the roofs of their cars or trucks.

Flying ice and snow may do no harm to the driver of the blanketed vehicle, but it can be incredibly dangerous to others. Connecticut’s move came after a woman and her two-year-old child were  hurt when ice flew off another car and shattered their windshield.

The AAA says that most states have laws that allow police to ticket drivers of cars covered with ice or snow, even if the law doesn’t spell that hazard out. But there’s no question that it’s the driver’s responsibility to make the car safe enough to be on the road.

Our autos experts offer the following advice:

• Run your car with the heat on while you’re clearing the outside. Use a long-handled brush or scraper to remove as much ice and snow as possible.
• If you can’t reach the roof easily use a sturdy step stool—but only if your shoes and the ground aren’t slippery. If the ground is too slick, work at the edges of the ice and lift it away from the roof in chunks.
• Don’t use road salt or directly scrape the car, both of which can damage the finish.
• Consider a warm spray at a car wash, particularly if you have a tall vehicle (though note that car washes have differing rules about allowing snow-covered cars to enter).

If a sheet of ice comes flying at you when you’re on the highway, don’t panic. Swerving and hitting another vehicle risks a serious accident, and will likely cause more damage than getting hit by the ice. Gently apply the brakes and don’t change lanes or stop abruptly without checking that it’s safe.

More to explore

• Winter driving tips
• Early warning signs of tire failure
• Guide to safe winter driving
• Four-wheel-drive vs. All-wheel-drive

 

Comments

[Jim Keeley]

I have found the two tires on the side facing the bright sun versus the two in the shade can be several PSI different. I set my tire pressure when they have not been driven AND when they have not been heated by the sun.