ABS, Traction Control and Winter Driving

Anti-lock brake systems (ABS) are nearly standard equipment on all new cars. In fact, most cars manufactured since the mid-90s probably have ABS, traction control and/or some other electronic stability control system, all of which are meant to improve stopping and stability and steering while braking, particularly on slippery (wet) roads. These features, when enabled and used properly, can help you more safely drive in winter weather conditions.

Systems Overview

Auto manufacturers have strategies at their disposal to help drivers improve their braking and steering capabilities.

ABS prevents skidding by ensuring that wheels continue to turn while braking rather than locking up and skidding. ABS involves an electronic monitoring system that measures brake pressure and wheel speed. When a wheel turns too slowly, brake pressure is decreased, and, conversely, when a wheel is turning too fast, brake pressure is increased. The ABS system can adjust brake pressure several times per second. ABS typically reduces stopping distance on dry roads, but increases stopping distances on wet roads. The major advantage, however, is that the driver has better steering control while braking with ABS, even on wet surfaces.

Traction Control keeps tires in contact with the road while accelerating. Through an electronic monitoring system, traction control prevents loss of traction by either reducing engine power to the wheels and/or applying ABS.

Electronic Stability Control monitors the direction of wheels in comparison to the steered direction. If the car is veering off course, the electronic stability control system applies ABS to the necessary wheel(s) to bring the wheel(s) back on course.

For (younger) drivers who may have never driven a car without these safety features, there is no adjustment. However, for drivers who learned to pump the brakes (cadence braking) and that you are supposed to steer into the direction of a spin, these technological developments may take some getting used to.

Improved Safety

Because ABS does increase stopping distance and traction control can prevent acceleration on loose surfaces (e.g. snow), some drivers believe that these features are hindrances to safe winter driving, but that’s not true. ABS does increase stopping distance on wet surfaces, but, for conscientious drivers who know that they need to slow down and allow more space between them and the car ahead, there’s hardly an adjustment to be made. In any case, it’s an adjustment that must be made because there is no way to disable ABS.

But, according to research from a number of agencies concerned with driving safety, there’s no reason to want to disable ABS because it is effective in preventing accidents. Statistical analyses of data from 1995 to 2007 (years after public information about how to use ABS correctly was available) show that ABS has significantly reduced (by 12%) the number of vehicle collisions on wet roads. Overall, ABS has reduced nonfatal passenger car crashes by 6% and light truck and van crashes by 8%.

The “trick” is to know how and when to make the best use of ABS and traction control systems:

  1. Give yourself more room! ABS will allow you to maintain steering control of your car, but it will need more space/time to do that. Just accept it, and back off the bumper of the car in front of you.
  2. Keep your traction control system on UNLESS you are trying to get your car out of a snow bank. The traction control system will reduce power to the wheels when it senses slipping, which it always will on a surface that gives. However, once you have gotten out of loose snow, turn the traction control back on so that your car can once again automatically help you to maintain directional control from the steering wheel.
  3. Review your Owner’s Manual so that you know how to enable/disable your traction control system and/or all/four-wheel drive.

No matter what features your vehicle has, there’s no substitute for common sense. In winter weather, slow down, give yourself and other drivers more space and stay alert!