The 6.6-liter LB7 Duramax Engine is produced by DMAX, a joint venture between GM and Isuzu in Moraine, Ohio. The Duramax Engine was released in late 2001 into the Chevrolet and GMC chassis vehicles. The LB7 Duramax Engine was replacing the old 6.5-L Detroit built engine which was a big jump forward in technology.