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Practice test 7 of 10

Maryland CDL — Air Brakes Practice Test 7

The Maryland 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.What creates the heat that can build up in a drum brake, and why does it matter?
  2. 2.At about what pressure does the governor normally stop the compressor from pumping (the cut-out point)?
  3. 3.On a tractor or straight truck, the spring brakes come fully on when air pressure drops into roughly what range?
  4. 4.What does the governor control on an air brake vehicle?
  5. 5.In which situations should you NOT use the parking brakes?
  6. 6.On large buses, at about what pressure do the low air pressure warning devices usually signal?
  7. 7.Why does correct brake adjustment matter so much to the emergency and parking brake function?
  8. 8.With the foot brake fully applied for one minute, what pressure loss is too much for a combination vehicle?
  9. 9.Which part of the air brake setup operates the brakes every time you press the pedal during ordinary driving?
  10. 10.What does the emergency brake system rely on to stop the vehicle if a brake failure occurs?

0 of 25 answered