• The 2007 Duramax 6600 is a General Motors diesel engine. This engine was designed to meet the 2007 EPA diesel engine requirements. Meeting all regulations, the Duramax 6600 featured emission equipment such as a diesel particulate filter, EGR cooler and active regeneration, which lowers fuel economy and cuts emission particulates by 90 percent. GM had produced earlier Duramax engines such as the LLY and LBZ, and followed them with the 2007 LMM, used in the Chevrolet Silverado HD, GMC Sierra HD, Chevrolet Kodiak and GMC Topkick.
  
  

General Specifications

• The 2007 Duramax was a 6.6-liter, V-8, turbo-diesel engine. It was engineered with a 90-degree "V" configuration with two banks of four cylinders. The cylinder bore was 4.06 inches and the piston stroke was 3.9 inches, yielding a displacement of 403 cubic inches.
  
  

Engine Material

• The Duramax 6.6L engine had a cast aluminum cylinder head and intake manifold, and a cast iron block. The exhaust manifold was made of cast nodular iron with a steel pipe extension, and the main bearing caps were made of cast nodular iron. The camshaft was made of steel, and the crankshaft was made of forged steel. The LMM engine's connecting rods were made of stress-fractured forged steel. The 6.6L engine weighed approximately 835 lb. and had an oil capacity of 10 quarts with filter.
  
  

Engine Injection, Fuel, Valves and Emissions

• The Duramax LMM engine had an overhead valve train with four valves per cylinder, and mechanical roller valve lifters. The fuel system was a 26,000-psi, Bosch high-pressure common rail with a CP3 injection pump. The emission controls for the LMM engine were a turbocharged, cooled exhaust gas recirculation, catalytic converter, diesel particulate filter and intake throttle.
  
  

Performance

• The Duramax LMM engine had a compression ratio of 16.8:1. This 6.6L engine could produce 365 horsepower at 3,100 rpm and 660 foot-pounds of torque at 1,800 rpm. The maximum speed for the LMM engine was 3,450 rpm.