New Jersey Air Brakes Practice Test

Under normal conditions, what is the use of brakes on a long steep downgrade?

1. They are the primary stopping power

2. They help prevent rollback

3. They are only a supplement to the braking effect of the engine

4. They are not necessary

The correct answer is: They are only a supplement to the braking effect of the engine

Using brakes on a long steep downgrade serves primarily to supplement the braking effect of the engine. When driving downhill, especially on long and steep grades, the vehicle's momentum increases due to gravity. Relying solely on the vehicle's brakes can lead to overheating and brake fade, which decreases braking effectiveness. Engine braking, achieved through downshifting, allows the engine to assist in slowing down the vehicle without putting excessive strain on the braking system. This technique helps maintain a safe speed on descents. Using the brakes in conjunction with engine braking creates a balanced approach that prevents the brakes from becoming overly stressed and helps maintain control throughout the descent. Hence, recognizing this relationship between engine braking and traditional brake use is crucial for safe operation on steeper grades.