putation has been inflated by car commercials that imply anti-locks can prevent crashes because of better stopping power under all conditions. Consumers very often haven't been shown cars with anti-locks performing on surfaces that are wet and slippery. This is the very surface on which anti-locks should make their main contribution.II. What Anti-lock brakes do and dont doMany car owners don't know how to use antilock brakes effectively and the manuals that come with their automobiles offer little help. Some of the manuals don't spell out how using antilock brakes is different from using regular brakes. Some manufacturers provide no instructions at all. Traditionally, drivers are trained to brake gently on slippery roads or to pump their brakes to avoid a skid. But it is firm, continuous brake pressure that is required to activate anti-locks, which should never be pumped. This is exactly what the antilock feature does for the driver automatically, it pumps the brakes many times a second. With the driver pumping antilock brakes during a skid, braking effectiveness may be reduced to the point of not having brakes at all.Because of misconceptions about the circumstances in which antilock brakes can help, it's useful to review what they can and cannot do. In normal braking, a vehicle slows as its wheels are gradually brought to a stop. Without antilock brakes, hard or emergency braking will cause the wheels to lock before the vehicle comes to a halt. In this case, some or all of the tires skid along the road. How the vehicle skids depends on the coefficient of friction, or drag factor, between the tires and the road surface. A vehicle may skid forward in a straight line or it may skid forward and drift to the right or left if the surface of the road is not level. Then again, a car may spin out. In any of these cases, the driver has effectively lost all control over the direction the car will travel. Antilock brakes can help...
