This product was last offered at the strikethrough price on
10-28-2026
This product was last offered at the strikethrough price on
10-28-2026
Over time, the factory valve cover hardware on M50, M50TU, M52, M52TU, M54, S50 (US), and S52 engines is subjected to continuous heat cycling, oil vapor, and moisture, causing original cap nuts to oxidize, corrode, or thread-strip during routine maintenance. Our Polished Valve Cover Cap Nut serves as a direct replacement designed to address these common failure points while improving upon overall engine bay aesthetics.
Because maintaining precise gasket compression is critical to preventing oil leaks, these cap nuts and washers are machined directly to OE-style dimensions. This exact fitment allows for direct compatibility with original and replacement valve cover studs (see T#55317643) and ensures the hardware can be torqued precisely to OEM specifications without guesswork. Manufactured to grade 8.8 structural strength standards, the hardware maintains the necessary clamp force required under normal and high-performance engine operating conditions.
To resist corrosion, both the cap nut and washer undergo an electroless nickel plating process during production. Unlike standard zinc coatings that dull or rust over time, electroless nickel provides a uniform layer of corrosion resistance that withstands long-term chemical exposure and extreme temperature swings while giving the hardware a polished, high-end appearance. Each cap nut assembly includes an OE rubber washer seal, ensuring a tight, leak-free barrier that prevents oil from escaping through the mounting studs.
From the factory, BMW S65 valve cover bolts feature integrated non-serviceable grommets. These rubber seals tend to weaken, becoming brittle after years of heat and oil exposure. Replacing these bolts and integrated grommets can total over $280
To address this issue, NRW has developed a solution: a silicone replica of the factory rubber grommet, boasting a superior heat resistance of 170 degrees Celsius compared to the original's 120 degrees Celsius. Each kit contains 26 grommets, enough to service both valve covers.
MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.
MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.
MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.
MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.
