LLY and LBZ Platforms
Along with having many of the same issues as the LB7, the LLY (2005 to early 2007) and LBZ (2007) also face a new set of possible untimely issues. Head gaskets have a tendency to fail early on, causing the heads to shift, which, if you’ve ever experienced a cracked head gasket, or other head problems, cause massive problems which must be repaired immediately. Every LLY and LBZ that Lind has come across has also had consistent issues with water pumps failing, and the CP3 injection pump failing anywhere from 175-200K miles, which is a reasonable, but still an expensive repair to prepare for.
Lind and the team at Left Coast Diesel have also seen consistent problems with trucks equipped with EGR systems.
“All of these smog trucks that have EGR systems are prone to failures in the vacuum pumps,” says Lind. “The pressure drops lower than specifications and shows up as a P0404 code. Drivers also experience idle fluctuations and lower power. Sometimes, the pump will ‘clack’ on the passenger side, but can sometimes be completely quiet, which is even more dangerous and very difficult to diagnose.”
Lastly, Lind has noticed failures in either the glow plug module or the glow plugs themselves. The truck will send an O3E P0380 code if one of the glow plugs has gone bad, but will also give this code if the module itself has failed. Lind suggests that LLY and LBZ Duramax owners check each glow plug before swapping out the module.