CDL GENERAL KNOWLEDGE
MASTERY TEST 2026 QUESTIONS AND
ANSWERS
1. What is the most important reason for doing a vehicle inspection?
A. To avoid being cited by Department of Transportation (DOT) inspectors.
B. To ensure the vehicle is clean for company branding.
C. To check if the fuel levels are sufficient for the trip.
D. Safety for yourself and other road users.
Answer: D
Conceptual Explanation: Safety is the primary reason for vehicle inspections. A vehicle
defect that is found during an inspection could save a life by preventing a breakdown or
crash.
2. What is the minimum tread depth for front tires on a commercial vehicle?
A. 4/32 inch
B. 2/32 inch
C. 6/32 inch
,D. 1/32 inch
Answer: A
Conceptual Explanation: Federal law requires at least 4/32 inch tread depth in every
major groove on front tires. Other tires require 2/32 inch.
3. Which of these is NOT a part of the basic ‘Control System’ of a commercial vehicle?
A. The Radio
B. The Clutch
C. The Accelerator
D. The Brakes
Answer: A
Conceptual Explanation: The radio is considered an accessory, not a primary control
system required for the operation of the vehicle like the steering, brakes, or accelerator.
4. How many red reflective triangles should you carry for emergencies?
A. One
B. Two
C. Four
D. Three
Answer: D
, Conceptual Explanation: Commercial vehicles must be equipped with three valid red
reflective triangles to mark the vehicle if it is stopped on the side of the road.
5. When double-clutching, what is the purpose of the first push of the clutch pedal?
A. To engage the gear synchronizers.
B. To put the transmission into neutral.
C. To stop the engine from stalling.
D. To increase engine RPM.
Answer: B
Conceptual Explanation: The first push of the clutch allows you to shift from the current
gear into neutral.
6. What should you do if you are being tailgated?
A. Speed up to increase the distance.
B. Flash your brake lights to warn the tailgater.
C. Increase your following distance from the vehicle in front of you.
D. Turn on your high beams to see better.
Answer: C
Conceptual Explanation: Increasing your following distance gives you more room to stop
slowly, which reduces the chance of the tailgater hitting you if you have to brake.
MASTERY TEST 2026 QUESTIONS AND
ANSWERS
1. What is the most important reason for doing a vehicle inspection?
A. To avoid being cited by Department of Transportation (DOT) inspectors.
B. To ensure the vehicle is clean for company branding.
C. To check if the fuel levels are sufficient for the trip.
D. Safety for yourself and other road users.
Answer: D
Conceptual Explanation: Safety is the primary reason for vehicle inspections. A vehicle
defect that is found during an inspection could save a life by preventing a breakdown or
crash.
2. What is the minimum tread depth for front tires on a commercial vehicle?
A. 4/32 inch
B. 2/32 inch
C. 6/32 inch
,D. 1/32 inch
Answer: A
Conceptual Explanation: Federal law requires at least 4/32 inch tread depth in every
major groove on front tires. Other tires require 2/32 inch.
3. Which of these is NOT a part of the basic ‘Control System’ of a commercial vehicle?
A. The Radio
B. The Clutch
C. The Accelerator
D. The Brakes
Answer: A
Conceptual Explanation: The radio is considered an accessory, not a primary control
system required for the operation of the vehicle like the steering, brakes, or accelerator.
4. How many red reflective triangles should you carry for emergencies?
A. One
B. Two
C. Four
D. Three
Answer: D
, Conceptual Explanation: Commercial vehicles must be equipped with three valid red
reflective triangles to mark the vehicle if it is stopped on the side of the road.
5. When double-clutching, what is the purpose of the first push of the clutch pedal?
A. To engage the gear synchronizers.
B. To put the transmission into neutral.
C. To stop the engine from stalling.
D. To increase engine RPM.
Answer: B
Conceptual Explanation: The first push of the clutch allows you to shift from the current
gear into neutral.
6. What should you do if you are being tailgated?
A. Speed up to increase the distance.
B. Flash your brake lights to warn the tailgater.
C. Increase your following distance from the vehicle in front of you.
D. Turn on your high beams to see better.
Answer: C
Conceptual Explanation: Increasing your following distance gives you more room to stop
slowly, which reduces the chance of the tailgater hitting you if you have to brake.
