It has been a mild winter here in Northern Virginia, but any time we get snowfall around here I get a lot of questions about four-wheel drive (4WD). Do you need 4WD to drive in the snow? The short answer is no.
Can 4WD be helpful in certain situations? Yes, it can.
How Four-Wheel Drive Works
All Wheel Drive (AWD) and 4WD are similar in that both functions engage all four tires in the driving process at the same time. Most of today’s SUVs and crossovers now come standard with AWD. The difference between AWD and 4WD is that AWD cannot be disengaged where 4WD is an option to engage.
Basically, both engage all four wheels at once. AWD is the version of 4WD that stays on, engages automatically, and is safe to use on both wet and dry pavement.
4WD has several options and is normally selected by the driver.
- 4WD Auto is the option that mimics AWD, safe to use on dry pavement and engages when slipping is detected.
- 4WD HI locks the front and rear tires together until disengaged and is intended for off road/slippery conditions.
- 4WD LOW provides greater torque and is meant for use at very slow speeds.
4WD and Snow
If all 4 wheels are engaged, why does it not help when driving in the snow? Because, when you are driving in snow, what you need to control the vehicle is contact with the pavement. If there is a layer of snow and ice between your tires and the road, its very similar to hydroplaning in the rain.
4WD is great for getting you going. All four tires are looking for traction to propel you forward, the likelihood of that happening with four wheels vs two is much greater. But, once you are moving, you face the same hazards as the two-wheel vehicles surrounding you.
Braking and Steering with 4WD in Snowy Conditions
4WD does not improve the vehicles breaking or steering capabilities. Once the tires have lost traction with the pavement, the ability to steer or stop has been greatly impeded. Just because you can get going, doesn’t mean you can stop or steer!
Once you are moving use great care and caution. Reduce speed and increase distance between vehicles. Never slam on the brakes. Apply brakes gently to bring down the speed.
Tires and Snow
The most important thing you can do to be prepared for winter is to ensure that you have good tires. Tire treads are designed to create the traction you need to stay in contact with the road in wet and snowy conditions. In severe or deep snow, chains can help create extra contact with the road.
Most auto repair shops, including Dulles South Chantilly Automotive, offer winter readiness checks. Have your car checked to ensure you are ready for old man winter and all the hazards he will throw your way.Tags: