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Free Wisconsin CDL Air Brakes Test 2025

Part of mandatory Entry-Level Driver Training Course Based on 2025 WI commercial driver's license manualAvailable in EN, ES
30questions
6mistakes allowed
80%passing score

The best way to stand out from the pack in Wisconsin as a truck driver is to have as many options as possible, when it comes to your qualifications and skills, and that means being able to drive a vehicle with air brakes. This exam features 30 multiple-choice questions based on the information that you’ve already studied in the Wisconsin Commercial Driver’s Manual, which is noted in the manual as possibly appearing on your exam. The more often you practice, by answering questions and reading each question’s accompanying explanation, the more comfortable you will be with air brake topics and information, and the more likely to pass your CDL air brake exam with flying colors. Then you’ll be on your way to success as you can drive a wider range of commercial vehicles. So, start practicing today, come back as often as possible, and good luck both now, and on your real Wisconsin air brake exam in the future!

4.36 out of 5 • 28 votes.

Perfect for

  • First-time WI CDL and CLP applicants
  • CDL holders adding endorsements
  • WI CDL renewal applicants
WI commercial driver's license

What to expect on the actual exam

How many questions25
How many correct answers to pass20
Passing score80%
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List of questions (classic view)

  1. Which of the following can cause brakes to fade or fail?
  2. The tractor protection valve
  3. Under which conditions are front wheel brakes good?
  4. Which of the following will be true about your brake function if your antilock braking system (ABS) fails?
  5. Which of the following is NOT part of the drum brake?
  6. Which of the following is NOT part of the air brake system?
  7. When should you drain your air tanks?
  8. How would you check your truck's slack adjusters?
  9. How can you tell if your vehicle is equipped with an antilock braking system (ABS)?
  10. What is the best way to test your vehicle's low air pressure warning signal?
  11. After the initial drop, the maximum acceptable leakage rates per minute are
  12. What is the best way to test if your vehicle's spring brakes come on automatically?
  13. If the air tanks are not drained,
  14. Which of the following should you do before leaving your vehicle unattended?
  15. Which vehicles must have low air pressure warning signals?
  16. An antilock braking system (ABS)
  17. When should you use the parking brake?
  18. Why must you pass a knowledge test on air brakes?
  19. At what measurement is the safety valve USUALLY set to open?
  20. Spring brakes are
  21. Which of the following are true about a dual air brake system?
  22. Which of the following is NOT part of the braking process when you're driving a tractor-trailer combination vehicle with an antilock braking system (ABS)?
  23. The purpose of a supply pressure gauge is
  24. Slack adjusters are
  25. How do brakes work on a long, steep downgrade?
  26. The low air pressure warning signal will come on before the pressure in the air tanks falls below
  27. A low pressure warning signal is required on
  28. All vehicles equipped with air brakes have
  29. With air brake-equipped vehicles, the parking brakes should be used
  30. The use of air brakes on a downgrade is only a supplement to the

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