When positioning the converter dolly for coupling, you should roll the converter dolly up to the rear trailer and stop when:

When positioning the converter dolly for coupling, you should roll the converter dolly up to the rear trailer and stop when:

• A. the fifth wheel is fully under the trailer apron plate.
• B. the rear trailer kingpin is about a foot from the jaw opening.
• C. you hear the pintle hook snap into place.
• D. the fifth wheel makes contact with the front of the trailer apron plate.

Answer: (D)

When coupling the converter dolly, stop when the dolly’s fifth wheel contacts the front edge of the trailer’s apron plate. This touchpoint ensures proper alignment and lets the locking mechanism engage correctly as you continue to couple. Stopping earlier won’t seat the fifth wheel properly, and stopping later can push against the apron or throw the alignment off. The other cues (like the pintle hook snapping or the kingpin’s distance from a jaw opening) aren’t the correct indicators for this coupling step.

When coupling the converter dolly, stop when the dolly’s fifth wheel contacts the front edge of the trailer’s apron plate. This touchpoint ensures proper alignment and lets the locking mechanism engage correctly as you continue to couple. Stopping earlier won’t seat the fifth wheel properly, and stopping later can push against the apron or throw the alignment off. The other cues (like the pintle hook snapping or the kingpin’s distance from a jaw opening) aren’t the correct indicators for this coupling step.