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Practice test 9 of 10

Oklahoma CDL — Air Brakes Practice Test 9

The Oklahoma 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.Compared with the instant action of hydraulic brakes, how long does air take to reach the brakes after the pedal is pushed?
  2. 2.At 55 mph on dry pavement, roughly how much distance does air brake lag add by itself?
  3. 3.While a vehicle is being driven, what holds the powerful springs of the spring brakes back?
  4. 4.Why should you avoid pressing the brake pedal while the spring brakes are already applied?
  5. 5.At roughly what pressure does the governor's cut-in point let the compressor start pumping again?
  6. 6.Before driving a vehicle with a dual air system, what minimum pressure should build in both the primary and secondary systems?
  7. 7.A visible low air pressure warning must switch on before tank pressure falls below what level?
  8. 8.What is the job of an alcohol evaporator in some air brake systems?
  9. 9.Which sequence describes the 'stab braking' method?
  10. 10.When checking a slack adjuster on an s-cam brake, about how far can it move before it likely needs adjusting?

0 of 25 answered