The all-new L5P Duramax 6.6L turbo-diesel engine advances the General Motors legacy of powerful, quiet, and durable diesels. The next-generation redesign offers more horsepower and torque than ever for easier, more confident hauling and trailering.

Along with a 19 percent increase in max torque over the previous Duramax 6.6L, the redesigned turbo-diesel's performance is quieter and smoother, reducing noise at idle by 38 percent.

6.6L L5P Features & Specifications

6.6L L5P Tech Specs
Type 6.6L V-8 L5P Turbo-Diesel
Displacement 403 ci
Compression Ratio 16.0:1
Valve Configuration Overhead
Valves Per Cylinder 4
Assembly Site Moraine, Ohio
Valve Lifters Mechanical roller
Firing Order 1 - 2 - 7 - 8 - 4 - 5 - 6 - 3
Bore x Stroke 103 x 99 mm
Fuel System DI with high-pressure common rail
Fuel Type Ultra-low-sulfur diesel and B20 biodiesel
Maximum Powered Speed 3450 rpm
Maximum Braking Speed 4800 rpm
Emissions Controls Cooled Exhaust Gas Recirculation (EGR), Selective Catalytic Reduction (SCR), Diesel Particulate Filter (DPF), intake throttle
Horsepower 445 hp (322 kW) @ 2800 rpm*
Torque 910 lb-ft (1234 Nm) @ 1600 rpm*
Block Cast iron
Cylinder Head Cast aluminum
Intake Manifold Cast aluminum
Exhaust Manifold Cast nodular iron with steel pipe extension
Main Bearing Caps Cast nodular iron
Crankshaft Forged steel
Camshaft Steel
Connecting Rods PM iron
Engine Oil Capacity 10 qt./9.5L