17-23 GM 6.6L L5P Duramax Mahle Cylinder Head Gasket Grade A

Fits: 2017-2023 GM 6.6L L5P Duramax

Multi-Layer Steel (MLS) head gasket in Grade A thickness (1.14-1.26mm) designed to deliver OE-level sealing for 2017-2023 GM 6.6L Duramax L5P diesel engines. Grade A is typically used when the block and heads require the thinnest service thickness after machining. Grade A (55522) is one of three service thickness specifications (A, B, C) for the GM 6.6L Duramax L5P D MLS head gaskets. Grade A is the thinnest option, used when the deck surfaces and piston protrusion measurements are at factory dimensions or slightly machined. Before selecting Grade A vs B or C, measure piston protrusion and head deck height after any head resurfacing — this determines which thickness maintains the correct quench and compression geometry.

Mahle: 55522