Air Brakes Practice Test for CDL Class A and B Exam

air brakes cdl

Air brakes are commonly used on heavy vehicles, such as trucks , trailers and buses. Here is how air brakes work on a truck trailer:

  1. An air compressor on the truck generates compressed air, which is stored in an air tank or reservoir.
  2. The driver applies the brakes by pressing on the brake pedal, which activates a brake valve.
  3. The brake valve sends a signal to open the brake chambers on the wheels of the trailer.
  4. The brake chambers contain a diaphragm, which is connected to a push rod. When the brake valve opens, the diaphragm expands and pushes the push rod outward.
  5. The push rod pushes against the brake shoes, which press against the drum brakes on the wheels. This creates friction and slows down the trailer.
  6. When the driver releases the brake pedal, the brake valve closes and the brake chambers release the compressed air. This allows the push rod to return to its original position, releasing the brake shoes and allowing the trailer to roll again.

Air Brakes Simple Questions For CDL Class A and B

Here are some questions that you might encounter on an air brakes exam for a commercial driver's license (CDL):

  1. How does an air brake system work?
  2. What is the maximum air pressure that should be allowed in the main air tank?
  3. How do you test the air brakes on a vehicle?
  4. What is a triple valve and what is its purpose in an air brake system?
  5. What should you do if the low air pressure warning light comes on while you are driving?
  6. How do you properly adjust the air brakes on a vehicle?
  7. What is a spring brake and how is it used in an air brake system?
  8. How should you handle an air brake system failure while driving?
  9. What is an automatic slack adjuster and how does it work?
  10. What are the different types of air brake systems and how do they differ from each other?

Remember to always consult the manufacturer's manual and local laws and regulations for specific information on the air brake system of the vehicle you will be driving.

Air Brakes Practice Test For CDL Class A and B

Welcome to the air brakes practice test for a commercial driver's license (CDL) class A or B! This test is designed to help you prepare for the air brakes endorsement exam that you will need to pass in order to operate a vehicle equipped with air brakes.

Air brakes are a critical component of any commercial vehicle, and it is important that you understand how they work and how to properly maintain and use them. The questions on this practice test are based on the material covered in the CDL manual and are designed to help you understand the concepts and principles related to air brakes.

To prepare for the actual test, it is recommended that you study the CDL manual thoroughly and practice with this and other practice tests. Good luck on your exam!

  • Code : It's not Endorsement
  • Number of questions : 25 questions
  • Pass rate : 80%
  • Pass Correct Answers : 20 Correct answer
  • How need It : Operate any Vehicle has air brake system  
  • How to pass the exam successfully: Practice well on the quiz below or read the CDL manual