Caterpillar 8C-5220 Press-In Wiper Seal is an OEM Cat hydraulic cylinder seal designed to wipe the rod and prevent contaminants from entering the cylinder as the rod retracts. The Cat Parts Store lists 8C-5220 as a press-in wiper seal and cross-references it to 311-9321, a 99.29 mm inner-diameter double‑lip wiper seal used on tilt cylinders to protect the hydraulic system and maintain reliable operation. The 311-9321 entry confirms the 99.29 mm ID and its double‑lip design for dirt exclusion. Verify fitment against your Cat cylinder head and rod dimensions in the Cat catalog or service manual to ensure correct replacement.
