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Practice quizzes / Illinois CDL Air Brakes Practice Questions - Illinois CDL Air Brakes Knowledge Test Exam / Question 99549
Practice question

In the air pressure buildup test for a dual air system, pressure should build from 85 to 100 psi within about how long at operating rpm?

  1. 10 seconds
  2. 45 seconds
  3. 3 minutes
  4. 10 minutes

Answer: B — 45 seconds

The correct answer is shown above. Try the full quiz for additional practice.

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