Kentucky CDL — Air Brakes Practice Test

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

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

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Kentucky 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
On a tractor or straight truck, spring brakes come fully on when air pressure drops into what range?
Test 2
25 questions · pass with 20
Which four elements add up to the total stopping distance for an air brake vehicle?
Test 3
25 questions · pass with 20
What produces the friction that slows an s-cam drum brake, and what side effect does it create?
Test 4
25 questions · pass with 20
What is the most common brake problem found during roadside inspections?
Test 5
25 questions · pass with 20
How should you test the service brakes before starting a trip?
Test 6
25 questions · pass with 20
When checking governor cut-in and cut-out during the final air brake check, at about what pressures should the compressor start and stop?
Test 7
25 questions · pass with 20
The brake pedal on an air brake vehicle is also known by what other names?
Test 8
25 questions · pass with 20
When checking governor cut-in and cut-out during the final air brake check, at about what pressures should the compressor start and stop?
Test 9
25 questions · pass with 20
When should you avoid setting the parking brakes?
Test 10
25 questions · pass with 20
If the air brake safety valve starts releasing air, what does that usually mean?