Description Left (Driver Side) Head Gasket for 2001-2016 GM 6.6L Duramax Options: Grade A (0.95mm) Grade B (1.00mm) Grade C (1.05mm) This premium Multi-Layer Steel (MLS) engine cylinder head gasket is designed to meet or exceed OEM specifications. Its heavy duty steel construction ensures a superior combustion seal and long term durability, providing the sealing needed to maintain proper compression ratios and prevent future leaks in high torque diesel applications. Features: Multi-Layer Steel (MLS) Gasket Integrated seal technology maintains compression in extreme temperatures Direct Fitment Guaranteed Fits LB7, LLY, LBZ, LMM, LML, and LGH Engine Models Driver (Left) Side Only How to Identify Your Current Gasket Grade: Before ordering, you can verify which gasket is currently installed on your engine. Each gasket features an identification tab that sticks out from between the engine block and the cylinder head. 1. Locate the Tab Driver Side (Left): Look near the front of the engine, typically tucked behind the power steering pump area or near the first exhaust manifold port. Passenger Side (Right): Look toward the rear of the engine, near the firewall. 2. Count the Holes or Notches Clean the tab with a bit of brake cleaner or a rag. You will see small circular holes or semi-circle/V-shaped notches punched into the metal to identify your grade: Grade A – 0 Holes or 1 Notch Grade B – 1 Hole or 2 Notches Grade C – 2 Holes or 3 Notches Reference # Grade A – 541.782, HC403L-A, 54583, 61-36465-00, 12637786 Grade B – 541.792, HC403L-B, 54584, 61-36465-10, 12637787 Grade C – 541.802, HC403L-C, 55027, 54585, 61-36465-20, 12637788
