Question 301 of 403

While inspecting the trailer coupling area, what should you check the fifth wheel locking jaws for?

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That they are loose enough to allow the trailer to slide slightly
That they are painted a bright color for visibility
That they match the color of the tractor frame
That they are fully closed and locked around the kingpin

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Correct answer to question 301 (General Knowledge): That they are fully closed and locked around the kingpin

Why

The locking jaws must fully close around the kingpin so the trailer cannot separate from the tractor. An open or partially locked jaw is an unsafe coupling that has to be fixed before driving.

Updated: November 2026

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While inspecting the trailer coupling area, what should you check the fifth wheel locking jaws for?

Why

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