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Practice test 4 of 10

Ohio CDL — Air Brakes Practice Test 4

The Ohio 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 does the manual say about manually adjusting an automatic slack adjuster just to bring it within limits?
  2. 2.While you are driving, the low-air-pressure warning suddenly lights up. What should you do?
  3. 3.Before checking the slack adjusters by hand, what should you do first?
  4. 4.What is the main benefit that antilock brakes (ABS) provide?
  5. 5.Because of brake lag, about how much extra distance does an air-brake vehicle travel at 55 mph on dry pavement compared with instantly acting brakes?
  6. 6.How do spring brakes actually hold a parked truck in place?
  7. 7.According to the manual, what is the most common brake defect found during roadside inspections?
  8. 8.What does a supply pressure gauge tell the driver?
  9. 9.An air brake setup is really three separate braking systems working together. Which three does the Ohio manual describe?
  10. 10.With the engine off and the parking brake released on a single vehicle, the air pressure drop should be less than how much in one minute?

0 of 25 answered