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 two, three or four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Utah Commercial Driver License Handbook. 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
13. 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.
14. Brake fade is a result of:
Explanation
If brakes are used too much, they will overheat and become less effective. This is referred to as brake fade.
15. The leakage rate for a triple combination vehicle with air brakes should be no more than ____ in one minute during a static leakage test.
Explanation
When performing a static leakage test on a triple combination vehicle with air brakes, the leakage rate should be no more than 5 psi in one minute. If the air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.
16. An air compressor governor controls:
Explanation
In an air brake system, the air compressor governor controls when the air compressor pumps air into the air storage tanks.
17. During an applied leakage test, the maximum leakage rate for a double combination vehicle is ____ in a minute.
Explanation
It is important to know the maximum air loss rate that is safe for your specific vehicle. A double combination vehicle should have a leakage rate no higher than 4 psi in a minute during an applied leakage test.
18. The ____ tells a driver how much pressure is in the air tanks.
Explanation
