This gasket seals the lift valve in the tractor's hydraulic system, preventing fluid leakage at the valve-to-housing interface. It sits between the valve body and the mounting surface, where it compresses to form a static seal under system pressure. A degraded gasket allows hydraulic oil to bypass the valve, reducing lift capacity and causing external drips that can lead to air ingestion. The gasket is manufactured to the original material specification, matching the compression set and fluid resistance required for the valve's sealing groove. On reinstallation, clean both sealing faces and replace the gasket; no sealant is needed.