Ford XS8Z-4215-AA Differential Pinion

Ford XS8Z-4215-AA Differential Pinion is an OEM Ford gear component that sits with the differential’s ring gear to transmit engine torque to the axle and enable wheel rotation. The part is identified by Ford part number XS8Z-4215-AA and is manufactured to Ford’s original specifications for tooth geometry, material, and finish to ensure proper engagement with the ring gear. As a replacement pinion, it is intended for use in Ford differentials that require this exact pinion; compatibility depends on the vehicle’s differential assembly and axle model. Because the pinion works in concert with the ring gear, correct installation and proper alignment, preload, and backlash are essential to maintain normal operation, reduce gear noise, and preserve longevity. This item is suitable for repairs or restoration where a genuine Ford differential pinion is required to maintain factory-like performance of the differential assembly. For best results, verify compatibility with your vehicle's model year and differential type using official Ford catalogs or a qualified technician.