Parking & Stopping

Study questions with answers

4 sample Parking & Stopping questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

1. 1. In which situations should you NOT use the parking brakes?

   Correct answer: When the brakes are very hot, or very wet in freezing temperatures

   Skip the parking brakes when the brakes are very hot from coming down a steep grade, or when they are very wet in freezing temperatures, since heat can damage them and freezing can lock the vehicle in place; use wheel chocks instead.

   Source: Maryland Commercial Driver License Manual (DL-151), Section 5.4.8 - Parking Brakes

2. 2. On newer air brake vehicles, how do you set the parking brakes?

   Correct answer: Pull out the yellow, diamond-shaped knob

   Newer vehicles use a yellow, diamond-shaped push-pull control knob; you pull it out to apply the parking (spring) brakes and push it in to release them.

   Source: Maryland Commercial Driver License Manual (DL-151), Section 5.1.15 - Parking Brake Controls

3. 3. Why must you drain the water and oil out of the air tanks?

   Correct answer: Because trapped water can freeze and lead to brake failure

   Compressed air carries moisture and a little compressor oil that settle at the bottom of the tank; in freezing conditions that water can turn to ice and knock out the brakes, so empty the tanks fully after each driving day.

   Source: Maryland Commercial Driver License Manual (DL-151), Section 5.1.4 - Air Tank Drains

4. 4. What should you always do before leaving your vehicle unattended?

   Correct answer: Apply the parking brakes or chock the wheels

   Whenever you step away from the vehicle, set the parking brakes or chock the wheels; otherwise it could roll off and injure someone or cause damage.

   Source: Maryland Commercial Driver License Manual (DL-151), Section 5.4.8 - Parking Brakes