Louisiana CDL — Air Brakes Practice Test

The Louisiana CDL — Air Brakes knowledge test has ~25 questions; you need ~20 correct (80%) to pass.

Or take one of 10 full-length practice tests

25 questions · pass with 20 correct. You get instant feedback and an explanation after every answer.

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The full-length test, with feedback and an explanation after every answer.

Louisiana CDL — Air Brakes practice tests

10 full-length practice tests, each with 25 questions and a pass mark of 20, like the real test. You see the answers and explanations after you grade.

Test 1
25 questions · pass with 20
The safety relief valve in the first air tank is usually set to open at what pressure?
Test 2
25 questions · pass with 20
If the air compressor has its own supply of oil, what should you do before driving?
Test 3
25 questions · pass with 20
On newer air-brake vehicles, how do you apply the parking brakes?
Test 4
25 questions · pass with 20
What is the main cause of brake fade?
Test 5
25 questions · pass with 20
Using the proper downhill braking method, when should you release the brakes?
Test 6
25 questions · pass with 20
Why is it important to drain the air tanks?
Test 7
25 questions · pass with 20
With the engine off, the parking brake released, and a fully charged system, the air pressure loss for a single vehicle should stay under what rate?
Test 8
25 questions · pass with 20
Which describes the 'stab braking' method?
Test 9
25 questions · pass with 20
When going down a long, steep grade, the service brakes should be used in what way?
Test 10
25 questions · pass with 20
On vehicles with dual parking control valves and a separate air tank to release the spring brakes, why must you plan your moves carefully?