GM/Chevrolet 6.6 403 - Duramax Diesel - Production Years 2007-2010

Description

Introduced midway through the 2007 production year, the LMM Duramax V8 replaced the LBZ Duramax.

During its run, the LMM produced 365 horsepower and 660 pound-feet of torque–and this was in spite of the tightening emissions standards for diesel engines at the time.

Engineers managed to increase performance to this degree by adding an intake airflow valve that regulates the Exhaust Gas Temperatures (EGTs). The head design was also revamped to have more efficient and effective coolant passage.

More efficient cooling was essential to this motor. Engineers added a Diesel Particulate Filter (DPF) and increased Exhaust Gas Recirculation (EGR) to cut down nitrogen oxide (NOx) emissions by 50 percent.

Chevy/GM introduced a larger EGR cooler to compensate for those changes.

Unfortunately, the aluminum-cast pistons on the LMM were prone to failure–just like its predecessor.