LMM Duramax Diesel

Related Topics:

Duramax LB7 Specs

Duramax LBZ Specs

Duramax LLY Specs

Duramax LML Specs

Allison 1000 Transmission

Duramax Diesel Buyers Guide













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6.6L Duramax LMM





Nearly identical to the LBZ, the LMM debuted midway into the 2007 model year. The slight variations between the LBZ and LMM gave a small increase in horsepower/torque output. The LMM was the first Duramax to use a diesel particulate filter (DPF) in order to drastically reduce particulate (soot) emissions. Reports suggest that the LMM Duramax was able to cut particulate emissions by 90 percent over the previous generation. 2010 was the last year that the LMM was available, as the LML was introduced for the 2011 model year.



6.6L Duramax LMM Specs


6.6L Duramax LMM, 90 degree V8, diesel.

Years Produced:

2007.5 - 2010

VIN Code:

6 (8th digit of VIN)


403 cubic inches, 6.6 liters.

Head/Block Material:

Aluminum cylinder heads, cast iron engine block.

Compression Ratio:

16.8 : 1

Firing Order:



4.06 inches.


3.90 inches.


Turbocharged & intercooled. Variable geometry turbocharger.


26,000 psi Bosch high pressure common rail with CP3 injection pump.


OHV (overhead valve), 4 valves per cylinder.

Oil Capacity:

10 quarts with filter.

Engine Weight:

Approximately 835 lbs.

Max Engine Speed:

3,450 rpm.

Emissions Equipment:

• Diesel Particluate filter (DPF); minimizes particulate emissions.
• Exhaust gas recirculation (EGR); reduces NOx emissions.
• Diesel oxidation catalyst (DOC); converts carbon monoxide into CO2 & water.

Peak Horsepower:

365 hp @ 3,100 rpm.

Peak Torque:

660 lb-ft @ 1,800 rpm.


Additional Duramax LMM Info

• Engine met strict 2007 EPA mandated emissions requirements for diesel engines by means of a diesel particulate filter (DPF). The diesel particulate filter was responsible for a significant decrease in fuel economy compared with previous models.
• The manual transmission option was retired before production of the LMM began - the engine was only offered mated to the Allison 1000 6 speed automatic transmission.
• The LMM offered only a slight increase in horsepower (+5 hp) and torque (+10 lb-ft) over the LBZ.
• During active regeneration, fuel is injected during the engine's exhaust stroke and burns in the exhaust system in order to provide the high temperatures necessary to clean the DPF (burn off the captured soot).
• The maximum boost provided by the variable geometry turbocharger is 20 psi (nominal), and the turbocharger can spin at speeds up to 120,000 rpm under full load.
• Two Duramax LMM engine options were available in GM's 4500/5500 medium duty trucks: a 300 hp/520 lb-ft or a 330 hp/620 lb-ft version.
• When used in GMC/Chevrolet Vans, the Duramax LMM was detuned to 250 hp and 460 lb-ft of torque. It was only offered with a HyrdaMatic 4L85-E 4 speed automatic transmission instead of the traditional Allison 1000.