6.6L Duramax Diesel Engine LLY
Debuting in the mid-2004 model year and used through 2005, the LLY was designed primarily to meet emissions goals. It was equipped with a variable vane Garrett turbocharger and was the first Duramax with an EGR (Exhaust Gas Recirculation) Valve. Due to the LB7's fuel injector problems, this new engine incorporated redesigned valve covers that did not have to be removed if fuel injectors needed replacing, saving labor costs. The LLY creates up to 300 bhp @ 3000 RPM and 520 lb ft torque @ 1600 RPM.