Threshold braking is best described as?

• A. Applying braking force just short of wheel lock
• B. Pumping brakes to avoid wheel lock
• C. Braking as hard as possible regardless of wheel lock
• D. Braking only after the car slows

Answer: (A)

Threshold braking means applying braking force just short of wheel lock, so the tires stay rolling and you preserve steering control while maximizing stopping power. Keeping the tires in rolling contact uses static friction, which is higher than the kinetic friction you get when wheels skid, so you can brake harder without losing direction. In cars with ABS, you still push the brake pedal firmly and hold it; the system automatically modulates pressure to stay at that near-lock limit without actually locking the wheels. The other approaches miss the key idea: pumping brakes is a modulation technique used on non-ABS systems and isn’t the continuous max effort of threshold braking; braking as hard as possible regardless of lock risks losing steering; delaying braking until the car slows wastes stopping distance.