2025 OK CDL Practice Test: Class B - Test 2
Based on
2025 OK CDL Handbook
8. How do air-operated disc brakes work?
A
They use an air compressor to feed air through a brake pipe into air tanks on each car.
B
All of the listed answers.
C
They use compressed air instead of hydraulic fluid.
D
When the engineer applied these brakes, the pipe filled with air and squeezed the brakes.