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Practice test 3 of 10

Virginia CDL — Air Brakes Practice Test 3

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.How is the air compressor normally driven?
  2. 2.At roughly what tank pressure does the governor 'cut out' and stop the compressor from pumping more air?
  3. 3.Why is repeatedly pressing and releasing the brake pedal for no reason a bad habit?
  4. 4.You should never leave a commercial vehicle unattended without doing what?
  5. 5.What are the four elements that make up total stopping distance for an air-brake vehicle?
  6. 6.When checking manual slack adjusters on s-cam brakes, roughly how much movement suggests the brakes need adjustment?
  7. 7.What is the most common brake problem found during roadside inspections?
  8. 8.What has testing shown about using the front wheel brakes on slippery surfaces?
  9. 9.On a tractor or straight truck, the spring brakes typically come fully on when air pressure falls to what range?
  10. 10.On newer air-brake vehicles, what does the parking-brake control usually look like and how is it used?

0 of 25 answered