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Practice test 8 of 10

Mississippi CDL — Air Brakes Practice Test 8

The Mississippi 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.If the low air warning signal does not work, what could happen in a single-circuit air brake system?
  2. 2.Your truck has air tanks larger than the minimum size, and building from 85 to 100 psi takes a bit longer than 45 seconds. What does the manual say?
  3. 3.You are driving an air-braked truck at 55 mph on dry pavement when you spot a hazard. With good traction and brakes, about how much road will you cover from seeing it to stopping?
  4. 4.You watch your air gauge climb to about 125 psi and then hold steady. What is the most likely reason it stopped rising?
  5. 5.Your brake lights stay dark when you apply the air brakes, even though the bulbs are good. Which air brake part is most likely involved?
  6. 6.A mechanic says the air disc brakes on your truck work like a big c-clamp. Which part, turned by the slack adjuster, does the clamping?
  7. 7.Some pre-1975 trucks carry a front brake limiting valve worked from the cab. What was it meant to do, and what is the catch?
  8. 8.A new driver says his truck has ABS, so he can follow closer because he will always stop shorter. What does the manual say?
  9. 9.Which statement about wedge brakes is accurate?
  10. 10.You find you need more and more application pressure to hold the same speed. Besides fading brakes, what else can cause this?

0 of 25 answered