4.86/5
7 votes
Click a star to add your vote
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
  • 0 Incorrect (6 allowed to pass)
  • 0 Correct
Restart
 
 
 
 
 
Back to Program Home
  • Updated for March 2025
  • Based on 2025 MT commercial driver's license manual

Free Montana CDL Air Brakes Test 2025

A CDL without an air brake restriction is essential for maximizing your job prospects, since most semi-trucks and tractor-trailers rely on air brakes. Failing to pass the Montana MVD CDL Air Brakes Knowledge Test results in an “L” restriction on your CDL, preventing you from operating vehicles equipped with air brakes. Failing the test also results in a one-day waiting period and a retest fee. Our Montana MVD CDL Air Brakes Practice Tests are designed to help you pass your knowledge exam on the first attempt.

From Montana’s rugged mountains to the frequent high winds and flooding on its plains, the terrain requires air brake-qualified drivers for heavy rigs. The deep snow and ice in winter compounds this need for a reliable air brake system. Major transportation routes in Montana include I-90 (a major freight corridor crossing the mountains), I-15 (a north-south route with steep inclines), I-94 (an eastern highway crucial for freight). The “L” restriction severely limits your driving options on these highways and the many jobs provided.

Industries across the Big Sky State that rely on drivers with the air brake qualification include agriculture, energy, mining, and tourism. Major companies requiring air brakes include CHS Inc. and RMA Energy in the agriculture sector and Montana Resources and ExxonMobil in the mining and energy sectors. XPO Logistics and UPS are major players in the freight and logistics industry that require air brake-qualified drivers. So do Greyhound Lines and Total Transportation in the tourism industry. Finally, school districts across the state use full-size air brake-equipped school buses, employing hundreds of qualified drivers. The “L” restriction makes operating CMVs equipped with air brakes illegal, eliminating the above-listed employment options.

The written Air Brakes knowledge test features multiple-choice questions based on the state’s CDL manual (Montana CDL Handbook 2025) and requires a minimum passing score of 80%. Our CDL Air Brakes Practice Tests cover all essential knowledge for the official MVD Air Brakes knowledge test. The information you learn will also help prepare you for your skills test, which includes inspecting components, testing for air pressure and leaks, and operating air brake-equipped vehicles.

Our Practice Tests are designed to resemble what you will face on the official test and offer real-time feedback on all responses. This scientifically proven approach improves material retention and ensures you’re prepared to pass the test.

  • Perfect for first-time and renewal CDL/CLP applicants, and those adding endorsements

What you need to know

4.86 out of 5 • 7 votes
9 min to complete
Available in EN and ES
Verified by Steven Litvintchouk, M.S., Chief Educational Researcher, Member of ACES. See our detailed commitment to accuracy and quality in our practice tests.

What to expect on the actual MT MVD exam

25

questions

20

correct answers to pass

80%

passing score

List of questions (classic view)

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

Your go-to, trusted source

Experience the Driving-Tests difference
Since our foundation in 2010, Driving-Tests.org has led the way in online driver's education, with over a decade of experience. Our dedicated experts, bringing together more than 50 years of collective expertise, have established us as the largest non-governmental organization in the U.S. solely focused on driver education. We go beyond the official manuals, offering unique interactive experiences and support like audio guides and an AI Assistant, to cater to different learning styles and needs.
Helping hundreds of thousands to ace their tests, our resources have earned a 4.7-star rating from over 14,500 reviews. Our goal is to make your path to becoming a confident driver as straightforward and effective as possible.
Ask AI Coach
Ask DMV Genie AI
new
    You test results are ready

    Pass the First Time – Guaranteed

    You’re moments away from your results.
    Before you view them, see how 1.15 million drivers used Premium to pass faster.

    • Real Exam-Like Montana Questions

      Get all exam-like questions seen on the real test.

    • 99.06% Pass Rate vs. 49% Average

      Most Premium users pass on their first try.

    • Money-Back Guarantee

      We stand behind you until you pass.

    Learn More & Guarantee My PassContinue to my results
    Opens in a new tab — your results are saved.