What is the purpose of a fifth wheel coupling?

The purpose of a fifth wheel coupling is to connect the trailer to the truck and allow for pivoting. This unique design creates a strong and secure connection between the towing vehicle and the trailer while facilitating necessary movement during turns. The fifth wheel allows the trailer to pivot around a vertical axis, which is essential for maneuverability, especially when navigating tight corners or changing directions. The design helps ensure that the coupling remains intact during transit while providing the flexibility needed for safe operation on the road.

The fifth wheel coupling does not serve to secure cargo within the trailer, stabilize the truck during high-speed travel, or improve fuel efficiency for combination vehicles. Each of those functions is addressed by different components or strategies within vehicle operation and cargo management.