Winter Driving Safety

Car basics for winter driving (Drivetrains)

Drivetrain types:

  • AWD-Full time power to all 4 tires via a center differential with higher gearing. Designed for good traction on roads in all conditions at all speeds.
  • 4WD-Part time power to all 4 tires (on demand with manual shiftover) via a transfer case. Normally have locking differentials w/ lower gearing designed for off-road use and extreme traction. Generally have two 4WD gear settings (4-Hi & 4-Lo). 4WD usage limited to non-highway speeds  (4-Hi) and crawling speeds for maximum traction (4-Lo).
  • Front wheel drive - Power to front tires only. Engine weight combined with power to the steering tires provides good traction & control in winter conditions.
  • Rear wheel drive - Power to rear wheels only. Lack of weight over rear, non-steering tires provides poor traction & control in winter conditions. (***Add weight over the rear axle to increase traction***)

Car basics for winter driving (Tires)

Tire types for snow:

  • All-Terrain / Mud-Terrain- Designed for 4WD vehicles and good for road, off-road, snow and mud. Generally have a larger & deeper tread pattern.
  • Snow tires鈥 Tires are made with a tackier rubber that stays flexible in cold weather and provides better traction. Generally have a larger & deeper tread pattern. They wear out faster in normal driving conditions.
    Tire label with a snowflake in a outline of a mountain peak with text "M + S" below it
    Outline of Mountain with snowflake inside it
  • Studded tires - Metal spikes embedded in the tire tread (normally on snow tires) that provide better traction in icy conditions. Limited by law to winter months (15 Nov -1 Apr) because they damage the roads by creating ruts.
  • Siping- Lateral cuts added to the tread of a tire that provides better traction in the snow and rain. They may reduce the life of the tire.
    Image of tire with sipes on it. Text reads Sipes with an arrow pointing to sipe on tire.
  • Snow 鈥渟ocks鈥 - Cloth coverings for tires designed for single emergency use that perform similar to snow tires. They are difficult to install and relatively expensive.
  • Snow chains - Traction chains that are strapped over the tires for traction in deeper snow. Chains go over the tires that provide power. (i.e. front tires for a Front wheel drive car). Speed limited to 25-30 MPH.
    Image of car in snow with chains on tires

Winter driving conditions

Types of winter driving conditions:

  • Black ice / Freezing rain - Usually invisible to the naked eye (look for crystalline reflection in headlights). Most dangerous condition as it is very easy to lose traction on all 4 tires. Studded tires work best.
Black ice on the road
  • Light snow (1-3鈥) - All Terrain and Snow tires work best.
cars driving on a road with light snow failing and on road
  • Heavy snow (>3鈥) - Use chains. 4WD vehicles with All-Terrain or Mud Terrain tires can still do well in these conditions without chains.    
road covered in snow with one car driving on it
  • City driving following a storm - 鈥淐leared鈥 roads will still have patches of black ice & ice/snow buildup. 4WD vehicles should be kept in the 4-Hi gear setting. Rear wheel drive vehicles should have weight added over the rear axle. Round-a-bouts, slopes and turns are the most dangerous areas; drive very slowly in these areas. 
rear of car on a road that has melting snow on it

Winter driving tips

  1. SLOW DOWN!- 25-30 mph max while in a storm. Below the speed limit in post storm conditions depending on conditions. Keep both hands on the wheel.
  2. Double following & stopping distances hands on the wheel.- Especially when approaching intersections or stopping on a downhill slope. Look out for other drivers who may have lost control.
  3. Gradually apply brakes and gas stopping. Don鈥檛 鈥減ump鈥 the brakes- Slow and steadily increasing brake pressure for . Slow and steadily increasing gas for starting.

***If you start sliding or lose traction:

  1. Take your foot off all pedals! (Yes鈥.both gas & brake)
  2. Calmly steer in the direction you want to go. Don鈥檛 oversteer.
  3. Gradually apply brake or gas once traction is re-established.

***Deschutes County offers skid car training to learn winter driving skills (4hrs / $90) ***