This pin secures the boom pivot joint on a loader, connecting the boom arm to the mounting bracket on the host tractor. It acts as the primary hinge point, allowing the boom to raise and lower while bearing the full static and dynamic load of the attachment. Wear on the pin or its mating bore creates slop in the joint, which leads to uneven lift motion and accelerated wear on the adjacent bushings. This original component is machined to the same diameter and hardness as the original assembly, so it maintains the correct clearance in the bore without requiring shimming. On installation, ensure the retaining hardware is torqued to specification to prevent axial movement during operation.