CDL · Air brakes
With the engine shut off and the brakes released, a combination vehicle's air pressure should drop by less than:
Correct answer: 3 psi per minute.
Answer options
- A2 psi per minute
- B3 psi per minute Correct
- C1 psi per minute
Why
When the brakes are released and the engine is off, a combination vehicle must lose under 3 psi per minute, while a single vehicle must stay under 2. A bigger drop means the air system is leaking and needs repair before the trip.
About this question
Topic: Air brakes License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of Checking and Using Air Brakes (15 questions). Take the full set and check your score.
Practice Checking and Using Air BrakesMore questions from Checking and Using Air Brakes
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