Caterpillar 9W7216 Duo-Cone Seal Assembly

The Caterpillar 9W7216 seal group is a duo-cone type mechanical face seal designed for heavy-duty undercarriage applications. It consists of two precision-ground metal sealing rings manufactured from alloy cast iron or forged steel with a hardness of HRC 65-72, and two elastomeric rubber toric rings (NBR or FKM) that provide axial loading and static sealing. This assembly retains lubricating oil within final drive housings, idlers, and rollers while excluding abrasive contaminants such as dirt, dust, and water. The seal operates in moderate-speed, high-abrasion environments typical of track-type machinery. It replaces OEM part numbers 2M2858, 5K6191, 077-5504, 9W5224, and 0787331. The component is a direct interchange for Caterpillar track loaders, hydraulic excavators, asphalt pavers, cold planers, and track-type tractors. Installation requires clean mating surfaces and proper lubrication during assembly to ensure optimal seal life and performance.