California CDL — Air Brakes Practice Test
The California 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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California 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
If your air tanks have manually operated drain valves, why must you drain them at the end of every driving day?
- Test 2
25 questions · pass with 20
How thin can brake linings wear before the handbook considers them dangerously thin?
- Test 3
25 questions · pass with 20
Some older vehicles have a front brake limiting valve with "normal" and "slippery" positions. What does the handbook say about using this control?
- Test 4
25 questions · pass with 20
The low air pressure warning comes on while you are driving. What should you do?
- Test 5
25 questions · pass with 20
How should you use the brake pedal to make a normal stop in a vehicle with air brakes?
- Test 6
25 questions · pass with 20
What must a driver do to hold a CDL without an air brake restriction?
- Test 7
25 questions · pass with 20
How do you test the service brakes during the final air brake check?
- Test 8
25 questions · pass with 20
For an average driver with good traction and brakes, about how far does a vehicle with air brakes need to stop from 55 mph?
- Test 9
25 questions · pass with 20
Why is it a bad habit to press and release the brake pedal over and over when you do not need to?
- Test 10
25 questions · pass with 20
What is "controlled braking" in an emergency stop?