Air Brakes
This endorsement is required for driving a vehicle with air brakes. To receive this endorsement, applicants must pass a written test. The test consists of 25 multiple choice questions. Each question has four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the New Jersey Commercial Driver Guide. Questions come from the chapter covering: Air Brakes. The Air Brakes endorsement may be used with the Class A, B or C CDL.
Number of Question
Passing Score
19. The air entering air storage tanks may contain:
Explanation
The air that enters air storage tanks in an air brake system usually contains a certain amount of water and compressor oil. Because accumulations of these materials can damage the braking system, tanks are equipped with drains to allow their removal.
20. The most common type of foundation brake used is the:
Explanation
The most common type of foundation brake is an s-cam drum brake.
21. Most heavy-duty vehicles use:
Explanation
Most heavy-duty vehicles use dual air brake systems. A dual system has two separate air brake systems with a single set of controls.
22. Brakes can get out of adjustment:
Explanation
Brakes are particularly prone to getting out out adjustment if they are hot. Use proper braking techniques to avoid letting your brakes overheat.
23. Air tank drains:
Explanation
In an air brake system, air tanks have drains to remove accumulations of water and compressor oil. Allowing water and oil to accumulate in the system could cause damage to the brakes. Manually operated drains should be used daily.
24. The air storage tanks:
Explanation
In an air brake system, the air storage tanks hold enough air for brakes to be used several times if the compressor stops working.
25. A one-way check valve:
Explanation
