CDL · Combination vehicles
When you look over a fifth-wheel coupling after hooking up, what should you see?
Correct answer: The upper and lower fifth wheel meet with no gap, and the locking jaws have closed around the kingpin shank.
Answer options
- AThe upper and lower fifth wheel meet with no gap, and the locking jaws have closed around the kingpin shank Correct
- BA gap of a few inches is left between the two fifth-wheel plates, and the locking jaws stay open
- CThe tractor's engine temperature reads normal, and the trailer tires hold the right air pressure
Why
A good coupling shows the two fifth-wheel plates flush, with no space between them, and the jaws locked around the kingpin. A gap can mean the kingpin is riding on top of closed jaws, and the trailer could break loose.
About this question
Topic: Combination vehicles License: CDL
Part of these practice sets:
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.
Practice Trailer Air Lines and CouplingMore questions from Trailer Air Lines and Coupling
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