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Practice test 4 of 10

Virginia CDL — Air Brakes Practice Test 4

The Virginia 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.On a long, steep downgrade, the service brakes should be used in what role?
  2. 2.If the safety relief valve lets air escape, what does that indicate?
  3. 3.A manually operated air-tank drain valve should be opened how often?
  4. 4.On a long grade, if you must keep increasing application pressure just to hold the same speed, what is most likely happening?
  5. 5.On a tractor or straight truck, the spring brakes typically come fully on when air pressure falls to what range?
  6. 6.When you press the pedal on an s-cam brake, what does the s-cam itself do?
  7. 7.How is the air compressor normally driven?
  8. 8.Even when a vehicle has an alcohol evaporator, what daily cold-weather task is still required (unless the tanks drain automatically)?
  9. 9.Why is repeatedly pressing and releasing the brake pedal for no reason a bad habit?
  10. 10.An air-brake-equipped vehicle is best described as having how many separate braking arrangements?

0 of 25 answered