Engine Valve Stem Oil Seal Set (24 PCS) BMW 135i 328i 335i 535i X5 N51 N52 N54 N55

This complete set of 24 valve stem oil seals is engineered to restore the internal sealing of the BMW N-series 24-valve cylinder heads. These seals are critical for controlling the amount of oil that lubricates the valve guides, preventing excess oil from entering the combustion chamber. Over time, heat cycles cause the original rubber to harden and crack, leading to blue smoke at startup, increased oil consumption, and carbon buildup on valves and spark plugs. This set includes premium high-temperature Viton seals designed to maintain flexibility and provide a superior seal under the extreme thermal loads of both naturally aspirated (N51/N52) and turbocharged (N54/N55) straight-six engines. Replacing these seals is an essential part of a top-end refresh to ensure clean combustion and maintain your BMW’s emissions performance.