CDL Air Brakes Knowledge Test 2024

CDL Air Brakes Knowledge Test 2024: Try our free  Commercial Driver’s License (CDL)  Endorsements Air Brakes Permit Test. There are 30 sample questions and answers for better CDL written exam preparation.

Air brakes use compressed air to make the brakes work. You can apply all the braking force you need to each of the wheels of a heavy vehicle, even units pulling two or three trailers. Air brakes are a safe way of stopping large vehicles if the brakes are well-maintained and used properly. However, you must know more about air brakes than you need to know about the simpler brake systems used on light vehicles.

CDL Air Brakes Knowledge Test 2024

CDL Air Brakes Knowledge Test 2024

Test Name CDL Practice Test 2024
Language English
License Endorsements Permit
Total Questions 30 MCQs
Test For Commercial Driver License
Test Preparation  Air Brake Endorsements
Country USA
Answers Yes
0 votes, 0 avg

CDL Air Brakes Knowledge Test

CDL Air Brakes Knowledge Test

1 / 30

Spring brakes do which of the following?

2 / 30

Which of the following statements is true?

3 / 30

In checking that the spring brakes come on automatically, you should not

4 / 30

Which of the following pumps air into the air storage tanks?

5 / 30

Foundation brakes are used

6 / 30

You have a fully-charged air system (125 psi). After turning off the engine and releasing the service brake, what are the maximum leakage rates per minute for both single and combination vehicles?

7 / 30

The braking power of spring brakes depends on

8 / 30

Air brakes use

9 / 30

What protects the tank and the rest of the air system from too much pressure?

10 / 30

During walkaround inspections of your vehicle, which parts of the air brake system should be checked?

11 / 30

The low-air-pressure warning light must come on before the air pressure in the tanks falls below what psi level?

12 / 30

When braking on downgrades,

13 / 30

Which of the following is a proper technique in using controlled braking?

14 / 30

The most common foundation brake is the

15 / 30

Why, on long downhill grades, do experts recommend using a low gear and light steady pressure instead of on-again, off-again braking?

16 / 30

A safety relief valve is installed in the first tank the air compressor pumps air to. The valve is usually set to open at what psi level?

17 / 30

How often should you drain your air tanks?

18 / 30

Air brake systems are three braking systems combined. They are

19 / 30

Pressing and releasing the brake pedal quickly and repeatedly

20 / 30

Most newer heavy-duty vehicles use dual air brake systems for safety. A dual air brake system has

21 / 30

ou are driving a vehicle at 55 mph on dry pavement under good traction and brake conditions. What is the approximate total stopping distance needed to bring your vehicle to a complete stop?

22 / 30

When should you NOT use the parking brakes?

23 / 30

If your truck or bus has dual parking control valves, you can use pressure from a separate tank to:

24 / 30

The main purpose of the alcohol evaporator is to

25 / 30

Which of the following tells you how much pressure there is in the air tanks?

26 / 30

During the walkaround inspection, if a slack adjuster moves slightly more than an inch where the push rod attaches to it, then

27 / 30

Before driving a vehicle with a dual air system, allow time for the air compressor to build up to 100 psi pressure in which of the following?

28 / 30

What should you do if the low-air-pressure warning comes on?

29 / 30

The brake system that applies and releases the brakes when the driver uses the brake pedal is the _____________ brake system.

30 / 30

Total stopping distance for air brakes is longer than that for hydraulic brakes due to ________ distance

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