---tab Description--- Description Upgrade your 2004.5–2010 GM LLY LBZ LMM 6.6L Duramax with a billet aluminum valve cover engineered for strength, sealing, and performance builds. The stock cast cover can crack, warp, or leak under heavy towing, high heat, or tuned engines. This CNC-machined replacement is 19.5mm thick, ensuring rigidity, improved sealing, and long-term durability. Designed with PCV flexibility, it allows reroute or delete configurations to reduce oil vapor re-entry into the intake. Ideal for performance builds, heavy haulers, or OEM replacements, this cover combines functional reliability with a clean, anodized finish for an upgraded engine bay appearance. Fitments 2004.5–2010 GM LLY LBZ LMM Chevrolet/GMC 2500HD 3500HD 6.6L Duramax Diesel Engines Key Features Billet Aluminum ConstructionStronger and more durable than OEM cast aluminum, resisting warping and cracking. CNC Precision, 19.5mm ThicknessReinforced structure ensures better sealing and deformation resistance. PCV OptionsIncludes dual fittings for reroute or external catch-can setups, reducing oil vapor contamination in the intake system. New Mounting HardwareComes with a complete set of installation bolts. Specifications Material Billet Aluminum (CNC-machined) Thickness 19.5mm Weight 6.19 kg Installation Location Engine top – replaces factory valve cover Fitment OEM bolt-on design ---tab FAQ--- FAQs Q: Why replace the OEM valve cover?A: Stock covers are prone to cracking, leaking, and poor sealing under heat or pressure. This billet cover is stronger, thicker, and designed to handle performance or heavy-duty use. Q: Does this include a new gasket?A: No, a new gasket is not included. You’ll need to reuse or replace the factory gasket during installation. Q: Can I retain the OEM fuel filter bracket?A: No. This cover does not have the factory standoffs. Bracket or harness modifications are required if you plan to reuse the OEM fuel filter mount. Q: What are the PCV options?A: The cover has two fittings—allowing you to reroute gases to a catch can, vent them to atmosphere, or adapt to your custom setup. Q: Does this product comply with emissions regulations?A: Since it modifies the PCV system, compliance depends on your local laws. Always check regulations before installation. Q: Will it improve engine performance?A: Indirectly. By preventing leaks and reducing oil vapor in the intake, it helps maintain turbo efficiency, intake cleanliness, and overall reliability. Q: Is installation difficult?A: It’s a direct bolt-on to the cylinder head, but due to PCV and bracket modifications, professional installation is recommended. Q: What finish options are available?A: Black, red, and silver anodized finishes, offering both durability and visual appeal. Q: Can I use this as an OEM replacement?A: Yes, it’s a suitable upgrade when replacing cracked, leaking, or warped OEM covers, even for daily use. Q: Does it work with aftermarket intakes?A: Yes. If deleting the PCV port, pairing...