After replacing all 8 glow plugs. The CEL is off and has stayed off. Doesn't make a lot of sense to me. Maybe replacing just the 4 on that side would have fixed it but I figured why take the chance on letting the others get old and possible break. It's cheap insurance.
2006 Chevrolet 2500HD 4X4 CCSB 6.6 Duramax LBZ