ACDelco 12747435 GM OE Cylinder Head Gasket (.99 mm)

The ACDelco 12747435 is a GM Original Equipment cylinder head gasket with a 0.99 mm compressed thickness, designed as a direct OE replacement for select GM engines. As part of ACDelco's GM OE gasket line, this part is manufactured to the same specifications, materials, and tolerances as the component originally installed at the factory.

The cylinder head gasket plays a critical role in engine integrity — it seals the combustion chambers and the coolant and oil passages between the cylinder head and the engine block, containing the heat and pressure generated during combustion. The 0.99 mm thickness variant is typically used when the cylinder head or block deck surface has been resurfaced, requiring a slightly thicker gasket to restore the correct compression ratio and head bolt clamping geometry.

Key Features:

• GM Original Equipment part — manufactured to OE specifications for fit, form, and function
• 0.99 mm compressed thickness for precise sealing on resurfaced or oversize applications
• Multi-layer steel (MLS) construction provides spring-like sealing performance under repeated combustion cycles
• Seals combustion chambers, coolant passages, and oil galleries between the head and block
• Designed, engineered, and tested to GM's rigorous quality standards
• Backed by General Motors as a recommended OE replacement component

The ACDelco 12747435 head gasket is sold individually and is the recommended replacement for GM vehicles requiring this specific thickness. Always verify surface finish and flatness specifications before installation to ensure proper sealing.