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Free Alabama CDL Air Brakes Test 2025

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

The Heart of Dixie features major highways like I-65, I-20/I-59, I-10, and I-85, filled with steep grades, heavy traffic, and long-haul demands that necessitate the use of air brakes in virtually all semi-trucks and tractor-trailers. If you plan to drive commercial motor vehicles (CMVs) equipped with air brakes and realize the importance of passing the official {state-agency} Air Brake Test, then our practice materials are needed. Without passing, your CDL will include the restriction “L,” preventing you from driving CMVs with air brakes. That’s quite a limitation on your job prospects. Alabama’s terrain includes rolling hills and flat plains, as well as steep grades and high humidity (in Birmingham and Huntsville), making air brake qualification vital for safe navigation. Preparing for this test is wise because air brake qualifications are a standard requirement for most companies due to the widespread use of this braking system.

In Alabama, there are multiple industries that rely on air brake-qualified drivers, including logistics and freight, charter bus services, educational services, manufacturing, and agriculture. Companies like UPS, FedEx, Old Dominion Freight Line, Greyhound, Southern Coaches, and Capital Trailways require air brake certifications. Even to drive a school bus in this state, you will likely need the qualification as most of them are now equipped with air brakes. Mercedes-Benz, Honda, and Hyundai depend on air brake-certified drivers. Also, poultry, timber, and cotton are regularly transported in vehicles equipped with air brakes. That’s a tremendous amount of opportunities, so let’s take a look at the requirements.

There are two parts to the test: the skills test and the knowledge test. The skills test will require you to physically inspect and identify the parts of an air brake system, as well as operate a vehicle equipped with air brakes. The multiple-choice knowledge test includes questions covering the state’s CDL manual and requires a score of 80% or higher to pass.

We have carefully designed our Alabama CDL Air Brakes Practice Tests to mimic the content you will face on the official DMV knowledge test. With our practice test questions and answers, you can learn the material quickly and feel confident as you near the day of your official exam. Once you feel prepared, simply schedule the knowledge test at the DMV, pay any fees, and take the test.

4.33 out of 5 • 33 votes.

Perfect for

  • First-time AL CDL and CLP applicants
  • CDL holders adding endorsements
  • AL CDL renewal applicants
AL 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. If the air tanks are not drained,
  2. The purpose of a supply pressure gauge is
  3. Which vehicles must have low air pressure warning signals?
  4. Spring brakes are
  5. Under which conditions are front wheel brakes good?
  6. How can you tell if your vehicle is equipped with an antilock braking system (ABS)?
  7. Which of the following are true about a dual air brake system?
  8. Slack adjusters are
  9. How would you check your truck's slack adjusters?
  10. What is the best way to test your vehicle's low air pressure warning signal?
  11. What is the best way to test if your vehicle's spring brakes come on automatically?
  12. After the initial drop, the maximum acceptable leakage rates per minute are
  13. An antilock braking system (ABS)
  14. Which of the following can cause brakes to fade or fail?
  15. How do brakes work on a long, steep downgrade?
  16. When should you use the parking brake?
  17. When should you drain your air tanks?
  18. 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)?
  19. Which of the following will be true about your brake function if your antilock braking system (ABS) fails?
  20. Which of the following should you do before leaving your vehicle unattended?
  21. Which of the following is NOT part of the air brake system?
  22. Which of the following is NOT part of the drum brake?
  23. At what measurement is the safety valve USUALLY set to open?
  24. The tractor protection valve
  25. In Alabama, why must you pass a knowledge test on air brakes?
  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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