However, if you are on the cusp of purchasing a used GM vehicle with an LB7 Duramax, you'll want to confirm whether or not it ...

[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.