Montana CDL Air Brakes Practice Test (MT) 2

5 out of 5 (36 votes)
80% Passing score
20 Questions
4 Mistakes allowed
Driving in MT presents unique challenges, from navigating the open plains to handling mountain roads. To ensure you're prepared for the CDL air brakes endorsement, our Montana CDL air brakes practice test is an essential resource. This Montana driver's license practice test is designed to complement your driver's education and ELDT courses, giving you an extra edge in understanding the material covered in the official state handbook. Our DMV air brake test features 20 multiple-choice questions that delve into the intricacies of air brake systems, covering components, operation, safety inspections, and stopping distance calculations. For example, you'll learn about dual air brake systems, which are crucial for safety as they provide a backup if one system fails. These topics are critical for anyone planning to drive commercial vehicles in Montana, where the terrain and weather can make driving conditions particularly demanding. The Montana CDL air brake practice test mimics the format of the actual DMV permit test, using multiple-choice and true or false questions. This familiar format helps you practice the process of eliminating incorrect answers to find the right one, a vital skill for passing the test. The questions are sourced directly from the official driver's manual, ensuring that the material you study is relevant and up-to-date. If it's not in the manual, it won't be on the test, so you can focus your efforts effectively. To pass this Montana air brakes CDL test, you'll need to answer at least 16 out of 20 questions correctly. This rigorous standard ensures that only well-prepared drivers are certified, which is essential for maintaining safety on Montana's roads. Whether you're maneuvering through snowy passes or traveling across wide-open highways, the knowledge you gain from this Montana CDL air brakes practice test will help you handle whatever the state's roads throw at you. So, gear up and take advantage of this comprehensive Montana permit test practice. It's your ticket to mastering the air brakes endorsement and driving confidently across Big Sky Country.
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Sample Montana Air Brakes Test Questions

Question 1

An air brake system includes service brakes, parking brakes, and which third system?

  1. A Foundation brake system
  2. B S-cam brake system
  3. C Foot-control system
  4. D Emergency brake system

Correct answer: D – Emergency brake system

The Montana CDL manual identifies three air brake systems: service, parking, and emergency. The service system operates during normal pedal braking, while the parking system holds the vehicle when parked. The emergency system uses parts of the service and parking systems to stop the vehicle during a brake system failure.

Source: Montana Commercial Driver License Manual 2026 — § 5, “Air Brakes”

Question 2

What normally keeps spring brakes released while an air-brake vehicle is moving?

  1. A Mechanical clamps
  2. B Wheel rotation
  3. C Spring pressure
  4. D Air pressure

Correct answer: D – Air pressure

Spring brakes supply the mechanical force used for parking and emergency braking. During normal driving, air pressure holds the powerful springs back, keeping the brakes released. If that pressure is removed because of driver action or air loss, the springs apply the brakes.

Source: Montana Commercial Driver License Manual 2026 — § 5.1.14, “Spring Brakes”

Question 3

While driving normally, what holds the powerful parking-brake springs back?

  1. A Air pressure
  2. B Spring pressure
  3. C Wheel speed
  4. D Vehicle weight

Correct answer: A – Air pressure

Air pressure prevents the spring brakes from applying while the vehicle is moving. When that pressure is released or lost, spring force applies the parking or emergency brakes. A major air-system leak can consequently cause the spring brakes to come on automatically.

Source: Montana Commercial Driver License Manual 2026 — § 5.1.14, “Spring Brakes”

Question 4

Which driving practice can directly cause brake fade?

  1. A Operating in heavy rain
  2. B Overusing the service brakes
  3. C Driving in congested traffic
  4. D Applying the parking brake after stopping

Correct answer: B – Overusing the service brakes

Repeated or prolonged use of the service brakes creates excessive heat. As the brakes overheat, drum expansion and changes in the linings reduce braking effectiveness, and continued overuse can eventually prevent the vehicle from slowing or stopping. Selecting the proper gear and using the engine’s braking effect help limit service-brake overheating.

Source: Montana Commercial Driver License Manual 2026 — § 5.4.5, “Brake Fading or Failure”

Question 5

If an air-brake vehicle has manual tank drains, when must the tanks be drained?

  1. A At the end of each day of driving
  2. B After every four hours on the road
  3. C Once each week
  4. D Every two weeks

Correct answer: A – At the end of each day of driving

Montana’s manual instructs drivers to drain manually operated air tanks at the end of each day of driving. Water and compressor oil collect at the bottom of the tanks and can harm the air brake system. Water may also freeze in cold weather and contribute to brake failure.

Source: Montana Commercial Driver License Manual 2026 — § 5.1.4, “Air Tank Drains”

Question 6

What should you do when the low-air-pressure warning activates while driving?

  1. A Stop and safely park as soon as possible
  2. B Shift to a higher gear
  3. C Make a hard brake application immediately
  4. D Open the trailer air-supply control

Correct answer: A – Stop and safely park as soon as possible

When the low-air-pressure warning activates, stop and safely park as soon as possible. Controlled braking is available only while sufficient air remains in the tanks. Do not wait for the spring brakes to apply automatically, because a loaded vehicle may require a long stopping distance and a lightly loaded vehicle may skid.

Source: Montana Commercial Driver License Manual 2026 — § 5.4.7, “Low Air Pressure”

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