Home › CDL Practice Tests › Combination Vehicles Questions › Question 9
What should there be between the upper part of the fifth wheel (the trailer apron plate) and the lower fifth wheel plate after coupling?
- A.At least two inches of gap
- B.A gap only on one side
- C.No visible gap; the plates should sit flush against each other
- D.As much gap as possible to allow turning
Correct answer
C. No visible gap; the plates should sit flush against each other
Why
A gap means the kingpin is sitting high in the jaws, a high coupling that can come loose. Flush contact shows the kingpin has entered at the correct height.
Manual topic: Combination Vehicles - Coupling · From the Combination Vehicles practice bank (CV-009).