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Practice test 10 of 10

Illinois CDL — Air Brakes Practice Test 10

The Illinois 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.Which brake defect turns up most often during roadside inspections?
  2. 2.If a leak drains all the air from the brake system, what do the spring brakes do?
  3. 3.Which foundation brake design is found on most vehicles with air brakes?
  4. 4.Pressing the brake pedal (the foot or treadle valve) down harder has what effect?
  5. 5.What tends to gather at the bottom of the air tanks, making draining necessary?
  6. 6.On a tractor or straight truck, spring brakes come fully on in what pressure range, and what should you do beforehand?
  7. 7.An air brake arrangement actually combines three distinct braking systems. Which set correctly names them?
  8. 8.When you check the governor, at roughly what pressures should the compressor start and stop pumping?
  9. 9.On some buses, what does a separate air tank tied to a dual parking control valve allow?
  10. 10.What is a modulating control valve used for?

0 of 25 answered