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Practice test 7 of 10

Missouri CDL — Air Brakes Practice Test 7

The Missouri 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 newer vehicles, how do you set the parking (spring) brakes?
  2. 2.In an s-cam brake, what does the s-cam do when the brakes are applied?
  3. 3.What happens when you press the brake pedal (treadle valve) down harder?
  4. 4.What does it indicate if the safety valve lets air escape?
  5. 5.In the recommended downgrade braking pattern, once your speed is about 5 mph below your safe speed, what do you do?
  6. 6.When should you skip setting the parking brakes and use wheel chocks instead?
  7. 7.At 55 mph on dry pavement, about how much distance does air brake lag add?
  8. 8.The governor lets the compressor start pumping again once tank pressure falls to about what level (cut-in)?
  9. 9.In a dual air system at operating rpm, pressure should climb from 85 to 100 psi within about how long?
  10. 10.How large a crack in a brake drum is unacceptable during inspection?

0 of 25 answered