Caterpillar Inc. CAT 5S-2106 Seal

CAT 5S-2106 Seal is a genuine Caterpillar lip-seal for rotating shafts, sized for a 50.80 mm (2.00 in) shaft diameter. The lip-type design is engineered to ride over the shaft on a film of oil, promoting long seal life and reliable lubrication retention. The Cat part number is 5S-2106 (often listed as 5S2106) and is sold through Cat® Parts Store as the authentic replacement option. This seal provides a precise fit for applications requiring a 50.80 mm shaft seal, aligning with Caterpillar’s standard lip-seal family to protect internal lubricants from contaminants. When replacing a worn seal on a Cat machine or hydraulic component that uses a 50.80 mm shaft, 5S-2106 offers a like-for-like Cat replacement that preserves sealing performance and compatibility with Cat housings. The specification emphasis is the shaft diameter and lip-seal design, ensuring correct fitment and minimizing downtime by using an authentic Caterpillar part.