4.120 MLS Head Gasket LH .051 6.4L Gen III Hemi

The 4.120 MLS Head Gasket LH .051 6.4L Gen III Hemi is engineered for serious builders and mechanics working with high-performance Dodge and Jeep applications powered by the legendary 6.4L Hemi platform. This left-hand gasket serves as the critical seal between your cylinder head and engine block, preventing combustion leakage and coolant bypass under extreme pressure and temperature conditions. Whether you're rebuilding a stock engine or pushing modified power levels, selecting the correct head gasket thickness is non-negotiable for reliability and longevity.

MLS (Multi-Layer Steel) head gaskets represent the gold standard for modern engine sealing, and this .051-inch thickness specification is precisely calculated to accommodate your Gen III Hemi's deck height and machining tolerances. The 4.120 bore diameter matches the cylinder specifications of the 6.4L platform, ensuring complete combustion chamber coverage and preventing hot spots or blow-by conditions. MLS construction provides superior reusability, thermal conductivity, and conformability compared to older composite designs, making it ideal for turbocharged, supercharged, or naturally aspirated builds where maintaining consistent compression is critical.

This left-side gasket is essential for any Gen III Hemi head gasket set replacement on 6.4L engines found in 2005–2023 Dodge Charger, Challenger, Magnum, and Jeep Grand Cherokee models. Proper installation requires careful torque sequencing with a calibrated torque wrench, following OEM specifications or your machine shop's recommendations based on head preparation and block condition. Invest in OEM-quality gaskets like this when your engine is apart—cutting corners on head gasket material will cost significantly more in downtime and potential engine damage later.