Maryland CDL — Air Brakes Practice Test

The Maryland 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.

Maryland 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
Which type of foundation brake is the most common on air brake vehicles?
Test 2
25 questions · pass with 20
Truck tractors built with air brakes on or after which date are required to have antilock brakes?
Test 3
25 questions · pass with 20
What is brake lag, the extra delay that air brakes add to stopping?
Test 4
25 questions · pass with 20
In a dual air brake system, which brakes does the primary system typically operate?
Test 5
25 questions · pass with 20
How does a wig wag warning device let the driver know the air pressure is getting low?
Test 6
25 questions · pass with 20
When the spring brakes finally set on a lightly loaded rig, or on a slick road surface, what extra danger appears?
Test 7
25 questions · pass with 20
What creates the heat that can build up in a drum brake, and why does it matter?
Test 8
25 questions · pass with 20
In a dual air brake system, which brakes does the primary system typically operate?
Test 9
25 questions · pass with 20
Which statement about what ABS does for your stopping is accurate?
Test 10
25 questions · pass with 20
Why must you drain the water and oil out of the air tanks?