Knowledge Test Class A

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question.. Read More

This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has four possible answer choices. Test questions come from the Colorado Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Combination, Doubles and Hazardous Materials. Endorsements that may be used with a Class A CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.

Number of Question
Passing Score

1. What kind of force must emergency brakes use?

Explanation
Because air pressure can eventually leak away, the emergency brakes in an air brake system must be held on by mechanical force.

2. In the event of an engine fire, you should not:

Explanation
In the event of an engine fire, you should turn off the engine as soon as possible. Do not open the hood if you can avoid it. Shoot foam through the louvers or from the vehicle’s underside.

3. Failing to drain the tanks in an air brake system can result in:

Explanation
In an air brake system, the air storage tanks must be drained to remove accumulated water and compressor oil. Failing to do this can cause damage. For example, water that has built up in the system could freeze in cold weather and cause brake failure.

4. The brake pedal is part of which braking system?

Explanation
The service brake system applies and releases the brakes when a driver presses the brake pedal while driving normally.

5. How many air storage tanks are used in an air brake system?

Explanation
Air storage tanks are used to hold compressed air. The number and size of air tanks in an air brake system varies among vehicles.

6. If carrying a heavy load that is slowing you down, you should:

Explanation
The right lanes of a roadway are generally intended for vehicles traveling more slowly than surrounding traffic. If being slowed down by a heavy load, you should stay in the right lane.

7. Accelerating roughly is:

Explanation
When accelerating, speed up smoothly and gradually so your vehicle does not jerk. Rough acceleration can cause mechanical damage.
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