The LLY engine uses a glow plug system with a control module operated by the glow plug control module (GPCM). The GPCM connects to each of the eight glow plugs individually.

The LBZ solved a lot of problems that plagued previous Duramax engines, but one notable issue did carry over from its LLY predecessor. A fault with the glow plug module would cause the glow plugs ...

GM has issued a special coverage bulletin for certain 2020 Chevy Silverado 1500 units that may have a fault cylinder 2 glow plug in their Duramax diesel engine.