CDL Air Brakes Practice Test Results

Question 1
50% answer correctly
Modulating control valves are used to:
Apply the spring brakes gradually
Switch between spring and air brakes
Apply the spring and air brakes together
Apply the air brakes gradually
Question 2
43% answer correctly
For vehicles that use air brakes, emergency and parking brakes:
Are not required
Must be a combination of mechanical and air brakes
Can only be air brakes
Must be mechanical brakes
Question 3
68% answer correctly
What are spring brakes used for?
Cab brakes
Emergency and parking brakes
Trailer brakes
Air brakes