This system is what connects the tractor and trailer.

This system is what connects the tractor and trailer.

• A. Transmission system
• B. Coupling system
• C. Kingpin system
• D. Suspension system

Answer: (B)

The connection between the tractor and trailer is made by the coupling system. This system includes the fifth wheel on the tractor and the kingpin on the trailer, which lock together to secure the two units while still allowing them to pivot for turns. The coupling system is specifically designed to hold the trailer to the tractor and keep them connected during operation. In contrast, the transmission system relates to the engine’s power delivery, and the suspension system handles ride and load support. The kingpin is a key component of the trailer part, but the overall connection is called the coupling system, not the kingpin system.

The connection between the tractor and trailer is made by the coupling system. This system includes the fifth wheel on the tractor and the kingpin on the trailer, which lock together to secure the two units while still allowing them to pivot for turns. The coupling system is specifically designed to hold the trailer to the tractor and keep them connected during operation.

In contrast, the transmission system relates to the engine’s power delivery, and the suspension system handles ride and load support. The kingpin is a key component of the trailer part, but the overall connection is called the coupling system, not the kingpin system.