The AERA Technical Committee offers the following information regarding a head gasket design change on 2001-06 GM 6.6L Duramax diesel engines. Special surface cleaning procedures must be followed to allow a proper seal when using the new design head gaskets along with a change in the torque angle specification.
A mid-year design change was made to the head gasket of the 2006 Duramax diesel engine. This second generation head gasket will service all 2001-06 vehicles,
including those that were built with the first generation head gaskets. The second generation head gasket does require a lower head bolt torque angle specification as well as special cleaning methods of the gasket surface.
The second generation gasket can be visually identified by its riveted construction as opposed to the crimped design of the first generation gasket.