6.6L Duramax LML

 

The LML Duramax is released for 2011 model General Motors & Chevrolet HD trucks. The latest version of the 6.6L Duramax, the LML uses advanced emissions equipment, including the use of diesel exhaust fluid injection, to reduce nitrogen oxide emission levels by 63 percent over LMM powered trucks. This allows the LML to exceed currently mandated federal emissions requirements & meet future future requirements as well. Not only is the LML the cleaniest Duramax in history; it is also the most powerul, being released with 397 horsepower & 765 lb-ft of torque.

6.6L LML Duramax Specifications:

Configuration:	90 degree V8
Displacement:	403 cubic inches, 6.6 liters
Block/Head material:	- Cast iron block - Aluminum cylinder heads
Compression Ratio:	16.8:1
Bore:	4.06 inches
Stroke:	3.90 inches
Aspiration:	Variable geometry turbocharger w/air-to-air intercooler
Valvetrain:	OHV, 4 valves per cylinder
Injection:	- Direct injection - Bosch high pressure common rail - 30,000 psi piezo actuated injectors.
Horsepower:	397 hp @ 3,000 RPM
Torque:	765 lb-ft @ 1,600 RPM

 

LML Duramax Features:

• B20 biodiesel compatible (20% biodiesel, 80% petroleum diesel mixture).
• Fuel mileage increased by 11% over 2010 models.
• Strengthened internals including:
  - Engine block for increased strength & engine noise reduction.
  - Main bearings.
  - Increased oil pump flow capacity for increased low RPM oil system operation.
  - Connecting rod pins for piston support.
  - Piston design for reduced reciprocating weight & piston strength.
• Factory engine brake with Allison 1000 transmission.
• GM states: "The engine has been developed to operate for at least 200,000 miles on a rough-duty cycle without the need for a major overhaul."

 

LML Duramax Emissions Equipment:

• Diesel particulate filter (DPF) nearly eliminates emissions of diesel soot. Active regeneration programming cleans the DPF periodically (estimated regen period every 700 miles, 300 miles less then previous systems, under normal operating conditions) by injecting diesel fuel into the exhaust stream, completely burning off soot captured in the DPF.
• Exhaust gas recirculation (EGR) with EGR cooler.
• Selective catalyst reduction (SCR) utilizing diesel exhaust fluid injection (DEF). DEF is a urea based fluid injected into the SCR to further reduce nitrogen oxide emissions. A DEF tank will need to be filled approx. every 5,000 miles (under normal operating conditions). Engine will enter into a limp-mode if DEF tank is empty.
• EGR cooler bypass to help eliminate soot deposits in the EGR cooler/system, which could potentially cause engine problems.

 

LGH Duramax:

The LGH is a detuned version of the LML Duramax designed specifically for chassic cab & box-delete vehicles. Since these vehicles are sold as "incomplete", special emissions requirements are applied. Therefore, the LGH has a few different features than the LML.

• 335 hp @ 3,100 RPM
• 685 lb-ft. @ 1,600 RPM
• Higher EGR cooling capacity.
• Revised turbocharger.
• Larger capacity SCR system.

Aside from these features, the LGH shares the same key design elements as the LML Duramax.