For a secure coupling, the fifth wheel jaws must grip which section of the kingpin?

Answer options

Why

The jaws have to wrap around the shank, the narrow neck of the kingpin, and not around its wider head. Jaws closed on the head are not truly locked, and the trailer could come loose.

About this question

Topic: Combination vehicles   License: CDL

Part of these practice sets:

• Trailer Air Lines and Coupling

Where it applies: Asked in every state.

Practice the whole set

This question is part of Trailer Air Lines and Coupling (28 questions). Take the full set and check your score.

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