Oil Galley Plug GM LS 99-13 Front 41/64

The Oil Galley Plug GM LS 99-13 Front 41/64 is a precision block component engineered for General Motors LS-series engines manufactured between 1999 and 2013. As an experienced mechanic rebuilding or modifying LS powerplants, you understand that the oil galley system is critical to engine longevity—proper sealing at all galleries prevents catastrophic oil loss and internal pressure drop. This front-mount plug, sized to the 41/64-inch specification, seals the factory oil passage that runs through the engine block, ensuring clean oil distribution to the crankshaft, camshaft, and valve train under full load.

DURA-BOND manufacturing produces this component to OEM standards, designed as a direct replacement for worn, stripped, or damaged original plugs. The 41/64-inch diameter accommodates the specific gallery bore found in early-generation LS blocks; improper sizing causes vacuum leaks in the oiling circuit and measurable pressure loss at idle and cruise. Installation is straightforward—the plug seats into the front block gallery with light thread-sealant application, requiring no special tools beyond a socket and wrench. DURA-BOND's engineering ensures consistent fitment across 1999–2013 LS variants, including the LS1, LS2, LS3, and truck-based LS platforms.

This plug is essential whether you're performing a full LS engine rebuild, upgrading to a high-capacity oil pump, or swapping an LS into a non-factory platform. Builders installing stroker cranks, high-flow cylinder heads, or aggressive cam profiles rely on sealed oil galleries to maintain system pressure and prevent bearing starvation. Verification of the 41/64-inch size against your specific block generation is recommended before purchase, though this dimension is standard for LS front-gallery applications. Stock this plug in your rebuild kit to avoid downtime and ensure your LS engine operates at peak efficiency and reliability.