CDL General Knowledge (Secs. 1, 2, 3, 12, 13) Questions
and Answers (Verified 100 Questions by Expert)
Course
Cdl
Question 1:
What is the primary purpose of the air brake system in a commercial vehicle?
A) To enhance fuel efficiency.
B) To provide emergency stopping power.
C) To assist with steering control.
D) To reduce noise while driving.
Answer: B) To provide emergency stopping power.
Rationale: The air brake system is crucial for safely stopping heavy vehicles, especially in
emergencies.
Question 2:
Which of the following is a key pre-trip inspection item?
A) Checking the color of the truck.
B) Ensuring all cargo is secure.
C) Adjusting the radio.
D) Washing the windshield.
Answer: B) Ensuring all cargo is secure.
Rationale: Securing cargo is vital for safety; loose cargo can shift during transport, causing
accidents.
Question 3:
What should you do if your vehicle begins to skid?
A) Steer sharply in the opposite direction.
B) Apply the brakes hard.
C) Steer in the direction you want to go and avoid overcorrecting.
D) Ignore the skid and continue driving.
Answer: C) Steer in the direction you want to go and avoid overcorrecting.
,Rationale: This helps regain control of the vehicle while preventing further loss of traction.
Question 4:
What is the minimum tread depth for steer tires on a commercial vehicle?
A) 1/32 inch
B) 2/32 inch
C) 4/32 inch
D) 6/32 inch
Answer: C) 4/32 inch.
Rationale: The minimum tread depth for steer tires is 4/32 inch to ensure adequate traction
and safety.
Question 5:
When should you use low gears while driving a heavy vehicle?
A) Only when starting on an uphill.
B) When driving downhill or when more power is needed for acceleration.
C) Only in residential areas.
D) Whenever you feel like it.
Answer: B) When driving downhill or when more power is needed for acceleration.
Rationale: Low gears help control speed on downhill grades and provide additional power
for heavy loads.
Question 6:
What is the function of the vehicle's suspension system?
A) To assist in steering.
B) To provide comfort to the driver.
C) To support the weight of the vehicle and absorb shocks.
D) To improve fuel efficiency.
Answer: C) To support the weight of the vehicle and absorb shocks.
Rationale: The suspension system is designed to provide stability and comfort while
maintaining contact with the road.
,Question 7:
What is the proper way to make a right turn in a commercial vehicle?
A) Turn sharply to get through quickly.
B) Signal your intention, move into the right lane, and make the turn wide.
C) Only use the left lane to turn right.
D) Speed up before making the turn.
Answer: B) Signal your intention, move into the right lane, and make the turn wide.
Rationale: Making wide right turns helps prevent collisions with pedestrians and other
vehicles.
Question 8:
What is the primary reason for using the “five-second rule” in following distances?
A) To ensure you can stop in time.
B) To help you drive faster.
C) To maintain a constant speed.
D) To save on fuel consumption.
Answer: A) To ensure you can stop in time.
Rationale: The five-second rule allows for adequate stopping distance, especially in adverse
conditions.
Question 9:
When should you use your headlights?
A) Only at night.
B) In all weather conditions, including rain, fog, and snow.
C) Only during the day.
D) Only when driving on highways.
Answer: B) In all weather conditions, including rain, fog, and snow.
Rationale: Headlights enhance visibility for the driver and help other vehicles see you,
improving safety.
, Question 10:
What does the “parking brake” do?
A) It is used to slow down while driving.
B) It holds the vehicle stationary when parked.
C) It enhances fuel efficiency.
D) It assists in steering.
Answer: B) It holds the vehicle stationary when parked.
Rationale: The parking brake is crucial for preventing the vehicle from rolling when parked,
especially on inclines.
Question 11:
What should you do if your vehicle begins to hydroplane?
A) Accelerate to regain control.
B) Steer straight and avoid sudden movements.
C) Slam on the brakes.
D) Turn sharply to regain control.
Answer: B) Steer straight and avoid sudden movements.
Rationale: Keeping the steering wheel steady helps prevent loss of control during
hydroplaning.
Question 12:
Which of the following is a key indicator that you may be driving too fast for road
conditions?
A) You can see clearly.
B) Other drivers are passing you.
C) You are frequently changing lanes.
D) You feel like you’re losing control of the vehicle.
Answer: D) You feel like you’re losing control of the vehicle.
Rationale: If you feel like you're losing control, it's a clear sign that you may be driving too
fast for conditions.
Question 13:
and Answers (Verified 100 Questions by Expert)
Course
Cdl
Question 1:
What is the primary purpose of the air brake system in a commercial vehicle?
A) To enhance fuel efficiency.
B) To provide emergency stopping power.
C) To assist with steering control.
D) To reduce noise while driving.
Answer: B) To provide emergency stopping power.
Rationale: The air brake system is crucial for safely stopping heavy vehicles, especially in
emergencies.
Question 2:
Which of the following is a key pre-trip inspection item?
A) Checking the color of the truck.
B) Ensuring all cargo is secure.
C) Adjusting the radio.
D) Washing the windshield.
Answer: B) Ensuring all cargo is secure.
Rationale: Securing cargo is vital for safety; loose cargo can shift during transport, causing
accidents.
Question 3:
What should you do if your vehicle begins to skid?
A) Steer sharply in the opposite direction.
B) Apply the brakes hard.
C) Steer in the direction you want to go and avoid overcorrecting.
D) Ignore the skid and continue driving.
Answer: C) Steer in the direction you want to go and avoid overcorrecting.
,Rationale: This helps regain control of the vehicle while preventing further loss of traction.
Question 4:
What is the minimum tread depth for steer tires on a commercial vehicle?
A) 1/32 inch
B) 2/32 inch
C) 4/32 inch
D) 6/32 inch
Answer: C) 4/32 inch.
Rationale: The minimum tread depth for steer tires is 4/32 inch to ensure adequate traction
and safety.
Question 5:
When should you use low gears while driving a heavy vehicle?
A) Only when starting on an uphill.
B) When driving downhill or when more power is needed for acceleration.
C) Only in residential areas.
D) Whenever you feel like it.
Answer: B) When driving downhill or when more power is needed for acceleration.
Rationale: Low gears help control speed on downhill grades and provide additional power
for heavy loads.
Question 6:
What is the function of the vehicle's suspension system?
A) To assist in steering.
B) To provide comfort to the driver.
C) To support the weight of the vehicle and absorb shocks.
D) To improve fuel efficiency.
Answer: C) To support the weight of the vehicle and absorb shocks.
Rationale: The suspension system is designed to provide stability and comfort while
maintaining contact with the road.
,Question 7:
What is the proper way to make a right turn in a commercial vehicle?
A) Turn sharply to get through quickly.
B) Signal your intention, move into the right lane, and make the turn wide.
C) Only use the left lane to turn right.
D) Speed up before making the turn.
Answer: B) Signal your intention, move into the right lane, and make the turn wide.
Rationale: Making wide right turns helps prevent collisions with pedestrians and other
vehicles.
Question 8:
What is the primary reason for using the “five-second rule” in following distances?
A) To ensure you can stop in time.
B) To help you drive faster.
C) To maintain a constant speed.
D) To save on fuel consumption.
Answer: A) To ensure you can stop in time.
Rationale: The five-second rule allows for adequate stopping distance, especially in adverse
conditions.
Question 9:
When should you use your headlights?
A) Only at night.
B) In all weather conditions, including rain, fog, and snow.
C) Only during the day.
D) Only when driving on highways.
Answer: B) In all weather conditions, including rain, fog, and snow.
Rationale: Headlights enhance visibility for the driver and help other vehicles see you,
improving safety.
, Question 10:
What does the “parking brake” do?
A) It is used to slow down while driving.
B) It holds the vehicle stationary when parked.
C) It enhances fuel efficiency.
D) It assists in steering.
Answer: B) It holds the vehicle stationary when parked.
Rationale: The parking brake is crucial for preventing the vehicle from rolling when parked,
especially on inclines.
Question 11:
What should you do if your vehicle begins to hydroplane?
A) Accelerate to regain control.
B) Steer straight and avoid sudden movements.
C) Slam on the brakes.
D) Turn sharply to regain control.
Answer: B) Steer straight and avoid sudden movements.
Rationale: Keeping the steering wheel steady helps prevent loss of control during
hydroplaning.
Question 12:
Which of the following is a key indicator that you may be driving too fast for road
conditions?
A) You can see clearly.
B) Other drivers are passing you.
C) You are frequently changing lanes.
D) You feel like you’re losing control of the vehicle.
Answer: D) You feel like you’re losing control of the vehicle.
Rationale: If you feel like you're losing control, it's a clear sign that you may be driving too
fast for conditions.
Question 13:
