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Practice test 4 of 10

Massachusetts CDL — Air Brakes Practice Test 4

The Massachusetts 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.While you are driving normally, what keeps the powerful springs of the spring brakes from applying the brakes?
  2. 2.As soon as the low-air warning light and buzzer come on, what is the correct action?
  3. 3.The total stopping distance for an air-brake vehicle is made up of four parts. Which list is correct?
  4. 4.What is a dual air brake system?
  5. 5.Air brakes actually combine three separate braking systems. Which answer names all three correctly?
  6. 6.Why should you avoid pushing the brake pedal while the spring brakes are already applied?
  7. 7.Why is it a poor habit to press and release the brake pedal more than you need to?
  8. 8.Air-brake trucks, buses, trailers, and converter dollies (other than truck tractors) built on or after which date must have antilock brakes?
  9. 9.Some buses have dual parking control valves fed by a small separate air tank. What is that tank for?
  10. 10.The safety relief valve sits in the first tank the compressor feeds. At about what pressure is it normally set to open?

0 of 25 answered