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Practice test 9 of 10

Louisiana CDL — Air Brakes Practice Test 9

The Louisiana CDL — Air Brakes knowledge test has ~25 questions; you need ~20 correct (80%) to pass.

This practice test follows that format: 25 questions, pass with 20 correct. Answer every page, then grade it to see the answers and explanations.

Questions 1–10 of 25

  1. 1.When going down a long, steep grade, the service brakes should be used in what way?
  2. 2.Using the proper downhill braking method, when should you release the brakes?
  3. 3.In a dual air system at operating rpm, the pressure should build from 85 to 100 psi within about how long?
  4. 4.Total stopping distance for an air-brake vehicle is made up of which factors?
  5. 5.What must you always do before leaving your vehicle unattended?
  6. 6.On a tractor or straight truck, the spring brakes come fully on when air pressure drops into what range?
  7. 7.At about what pressure does the governor tell the compressor to stop pumping air?
  8. 8.The governor lets the compressor resume pumping at roughly what pressure?
  9. 9.What does an antilock braking system (ABS) do during hard braking?
  10. 10.What is the purpose of an alcohol evaporator in an air brake system?

0 of 25 answered