The version was introduced in 1992 to replace the 6.2. Most 6.5s are equipped with a turbo. This engine was never meant to be a power and torque competitor with Ford/International and Dodge/Cummins, but rather a simply designed workhorse engine that made credible power, achieved decent fuel economy and met emission standards in half-ton trucks. The Duramax 6600 replaced the 6.5 in light trucks beginning in 2001 and the C3500HD medium duty cab and chassis (replaced by C4500 Kodiak/Topkick) and vans beginning in 2003, but the 6.5 (6500 Optimizer) is still produced by AM General for the HMMWV.