[Image by Joe Haupt via Flickr | Cropped and scaled | CC BY-SA 2.0] In mid-2004, Chevy followed up the LB7 with the LLY Duramax, which boasted a new injector design that made servicing much easier.

GM redesigned the engine's injectors for the Duramax LLY, which meant that owners and mechanics could now service them externally. This eliminated much of the hassle involved in replacing LB7 ...