Parking & Stopping

Study questions with answers

5 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. What tends to gather at the bottom of the air tanks, making draining necessary?

   Correct answer: Water and compressor oil

   Compressed air carries water and a little compressor oil, which settle in the tank bottoms and must be drained out.

   Source: Illinois CDL Study Guide — Section 5.1.4: Air Tank Drains

2. 2. On newer air-brake vehicles, what does the parking brake control look like and how do you use it?

   Correct answer: A yellow diamond-shaped knob you pull out to apply and push in to release

   The modern parking brake control is a yellow, diamond-shaped push-pull knob: pull out to apply, push in to release.

   Source: Illinois CDL Study Guide — Section 5.1.15: Parking Brake Controls

3. 3. With manually operated drain valves, how often are you responsible for emptying the tanks?

   Correct answer: At the close of every driving day

   Manual valves drain nothing on their own, so you have to empty the tanks each day at the end of driving.

   Source: Illinois CDL Study Guide — Section 5.1.4: Air Tank Drains

4. 4. How do you verify that the parking brake will hold?

   Correct answer: Set it, then gently pull against it in a low gear

   Set the parking brake and gently tug against it in a low gear to confirm it holds the vehicle.

   Source: Illinois CDL Study Guide — Section 5.3.3: Final Air Brake Check

5. 5. Why should you avoid stepping on the brake pedal while the spring brakes are already set?

   Correct answer: The combined spring and air forces could damage the brakes

   Adding air pressure on top of the applied springs can damage the brakes, so avoid pressing the pedal when the spring brakes are on.

   Source: Illinois CDL Study Guide — Section 5.1.15: Parking Brake Controls