That changeover occurred just a few years after GM began producing Duramax engines, with the LLY arriving in mid-2004. If you want to figure out which of these Duramax variants is under the hood ...

The fuel system was another critical aspect of improvement, with the LBZ receiving multiple new fuel system components. While the common-rail fuel system and high-pressure fuel injectors were a ...

Early in the history of Duramax engines, GM changed the LB7 series of engines to LLY, but it can be difficult to tell them apart. Here’s how.