What must be done with the rear shut-off valves before air can reach the second trailer's air tanks?

Answer options

Why

Air for the second trailer has to pass through the back of the first one, so the first trailer's rear valves must be open. The valves at the back of the last trailer stay closed so the air is held in the system instead of escaping.

About this question

Topic: Doubles and triples   License: CDL

Part of these practice sets:

• Coupling Doubles and Converter Dollies

Where it applies: Asked in every state.

Practice the whole set

This question is part of Coupling Doubles and Converter Dollies (28 questions). Take the full set and check your score.

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