RK0676
Kingpin Assembly
SAF-Holland

The kingpin assembly serves as the central pivot and load-bearing interface between the tractor and trailer, forming the primary connection that enables safe articulation under dynamic highway conditions. Constructed from high-strength steel, the 2 inch diameter pin is designed to resist wear, bending moments, and surface fatigue encountered during long-haul operation. This assembly supports pivotal rotation, enabling steering responsiveness and stable trailer tracking across a wide range of speeds and load scenarios. Replacement of worn or damaged kingpins is critical to maintaining coupling integrity, braking efficiency, and overall vehicle safety. The component is integral to heavy-duty coupling systems and interacts with yokes, bushings, and locking heads to preserve proper clearance and engagement. VMRS code 059-001-024 situates it within kingpin-focused maintenance, and category context (42792) anchors its role in the front-axle/kingpin family of components essential for safe trailer hitch operation.