You’re driving your 4x4 on a snowy road when, suddenly, you notice the road bends to the right. You slam on the brakes and crank the steering wheel to the right. But the truck continues to plow a straight line; in fact, it’s headed for a tree. Would you know how to handle this? Control of a 4x4 is determined by three factors: steering, acceleration, and braking. You can use all three in ­slippery conditions, but only one at a time. • Here are two of the most common situations you may face on snow or gravel.