Traffic Laws

Study questions with answers

7 sample Traffic Laws questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

1. 1. How often must you empty air tanks that have only manual drain valves?

   Correct answer: When you finish driving for the day

   Manually drained tanks need their water and oil released once you finish driving for the day.

   Source: 5.1.4 Air Tank Drains

2. 2. Since which year have all newly built vehicles come with automatic slack adjusters?

   Correct answer: 1994

   The manual states that every vehicle built since 1994 comes with automatic slack adjusters.

   Source: 5.3.2 Walk-around Inspection

3. 3. Which of these is required equipment on every vehicle with air brakes?

   Correct answer: A low-air-pressure warning signal

   A low-air-pressure warning signal is mandatory on air-brake vehicles; the other items listed are optional add-ons.

   Source: 5.1.11 Low Air Pressure Warning

4. 4. Air-brake truck tractors must have antilock brakes if built on or after which date?

   Correct answer: March 1, 1997

   The rule requires ABS on air-brake truck tractors manufactured on or after March 1, 1997.

   Source: 5.1.16 Antilock Braking Systems (ABS)

5. 5. Other air-brake vehicles such as trucks, buses, and trailers must have ABS if built on or after when?

   Correct answer: March 1, 1998

   Trucks, buses, trailers, and converter dollies with air brakes built on or after March 1, 1998 are required to carry antilock brakes.

   Source: 5.1.16 Antilock Braking Systems (ABS)

6. 6. With the engine off and the parking brake released, a single vehicle's air-loss rate should stay under what?

   Correct answer: 2 psi in one minute

   For a single vehicle, the pressure drop with brakes released should be less than 2 psi per minute; more than that means a leak.

   Source: 5.3.3 Test Air Leakage Rate

7. 7. On an older vehicle with a front brake limiting valve, where should the cab control stay for full stopping power?

   Correct answer: In the 'normal' setting

   Front-wheel braking helps in all conditions, so the control should stay in the 'normal' position to keep full stopping power.

   Source: 5.1.13 Front Brake Limiting Valve