Some trucks have dual parking control valves that can use air stored in a separate tank. What is that stored air used for?

Answer options

Why

On vehicles with dual parking control valves, pushing in a spring-loaded control sends air from the separate tank to release the spring brakes, so you can move the vehicle a short way in an emergency. That tank holds only enough air to do this a few times, so plan the move carefully.

About this question

Topic: Air brakes   License: CDL

Part of these practice sets:

• Checking and Using Air Brakes

Where it applies: Asked in every state.

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This question is part of Checking and Using Air Brakes (15 questions). Take the full set and check your score.

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