ACDelco 97229043 OE Rear Adapter Housing Water Housing Cover Gasket, 2001-2020 GM 6.6L Duramax LB7 LLY LBZ LMM LML LGH L5P

ACDelco 97229043 OE Rear Adapter Housing Water Housing Cover Gasket.
For 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 GM 6.6L Duramax
LB7 LLY LBZ LMM LML LGH L5P

Used on rear engine adapter on pass side. Coolant passage block off plate

If your engine is apart or out of the truck, replace this gasket. It can leak sometimes and its a bear to get to with stock downpipe in place.