Mississippi CDL — Air Brakes Practice Test

The Mississippi 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.

Mississippi 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
Your truck is nearly empty and the road is wet when a leak drains the air system and the spring brakes come on. What does the manual warn could happen?
Test 2
25 questions · pass with 20
Total stopping distance for a vehicle with air brakes is made up of four distances. Which of these is NOT one of them?
Test 3
25 questions · pass with 20
Your dual air brake truck has only one supply pressure gauge in the cab. How can that one gauge show both halves of the system?
Test 4
25 questions · pass with 20
Your truck has a brake system failure. To bring it to a stop, the emergency brake system relies on parts of which other systems?
Test 5
25 questions · pass with 20
A new driver says his truck has ABS, so he can follow closer because he will always stop shorter. What does the manual say?
Test 6
25 questions · pass with 20
In stop-and-go traffic you keep pressing and releasing the brake pedal far more than you need to. What could this lead to?
Test 7
25 questions · pass with 20
Which sequence matches the manual's normal stop in an air-braked truck with a manual transmission?
Test 8
25 questions · pass with 20
If the low air warning signal does not work, what could happen in a single-circuit air brake system?
Test 9
25 questions · pass with 20
In stop-and-go traffic you keep pressing and releasing the brake pedal far more than you need to. What could this lead to?
Test 10
25 questions · pass with 20
During the governor check with the engine at a fast idle, how can you tell the governor has cut out the compressor?