Excavator Pump Parts A10VSO71 Piston Shoe For Hydraulic Oil Pump Spare Parts Force Transmission & Self-Adapting Angular Motion The piston moves linearly back and forth inside the cylinder block, and the swash plate is a fixed inclined component. Utilizing spherical hinge structure, the piston shoe swings freely following swash plate angle and transfers piston axial thrust smoothly to the swash plate. Without piston shoes, point contact emerges between piston ball head and