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Practice test 3 of 10

Florida CDL — Air Brakes Practice Test 3

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

This practice test follows that format: 25 questions, pass with 20 correct. Answer every page, then grade it to see the answers and explanations.

Questions 1–10 of 25

  1. 1.Unlike hydraulic brakes, air brakes have a built-in delay because air must travel through the lines. About how long is that brake lag?
  2. 2.You are stab braking during an emergency stop and the wheels lock up. When do you put the brakes back on?
  3. 3.As you use the brakes and air pressure in the tanks drops, at roughly what pressure does the governor put the compressor back to work?
  4. 4.What information does the supply pressure gauge on the dash give you?
  5. 5.Using the proper braking technique on a long downgrade, you have reached your safe speed of 40 mph in a low gear. What comes next?
  6. 6.Why must air storage tanks be drained regularly if they only have manual drain valves?
  7. 7.During your pre-trip you find cracked brake drums and an audible air leak at a brake chamber. What are you required to do?
  8. 8.When you check air pressure build-up on a vehicle with a dual air system, the pressure should rise from 85 to 100 psi within:
  9. 9.What does the stop light switch do in an air brake system?
  10. 10.Your tractor has antilock brakes but the trailer behind it does not, and during a hard stop the trailer begins swinging out. What is the right response?

0 of 25 answered