Product Overview This variable displacement axial piston hydraulic pump is designed for the CAT D8R, D8R II, and D8N track-type tractors. It delivers reliable hydraulic power for blade lifting, tilting, steering, and all working hydraulic circuits on the machine. Part Number 139-4151 Interchange Part Numbers 0R-4612, 6E-1661 Pump Type Variable displacement axial piston pump Compatible Machines CAT D8R, D8R II, D8N track-type tractors Application Blade lifting, tilting,