When coupling a rear trailer to a converter dolly, position the trailer slightly lower than the center of the fifth wheel for a smoother and controlled coupling process.
The correct answer is option B "slightly lower than".
When preparing to couple a rear trailer to a converter dolly, it is essential to consider the alignment of the trailer height with the center of the fifth wheel. The correct choice among the options is B. "slightly lower than."
Optimal coupling involves aligning the trailer height slightly lower than the center of the fifth wheel. This positioning facilitates a smoother and more effective coupling process. When the trailer is slightly lower, it allows for a controlled descent onto the fifth wheel, ensuring a secure connection without excessive force or misalignment.
If the trailer height were the same as or slightly higher than the center of the fifth wheel, it could lead to difficulties in achieving a proper coupling. Matching heights might result in resistance and challenges in aligning the kingpin of the trailer with the fifth wheel, while a height slightly higher than the center could make the coupling process less controlled.
The term "perpendicular to" (Option D) is not applicable in this context, as the height relationship between the trailer and the fifth wheel is more appropriately described as being slightly lower than for optimal coupling.
In summary, when preparing to couple a rear trailer to a converter dolly, it is advisable to position the trailer height slightly lower than the center of the fifth wheel for a smoother and more controlled coupling process.