Duramax V8 engine

Duramax Diesel engine

Manufacturer	DMAX
Production	2001–
Predecessor	6.2 and 6.5 L Detroit Diesel

The Duramax is General Motors' diesel engine family for large trucks, designed by Isuzu. The 6.6 liter Duramax is produced by DMAX, a joint venture between GM and Isuzu in Moraine, Ohio. This engine was initially installed in 2001 MY Chevy and GMC trucks and has been the engine of choice since that time. In 2006, production at Moraine was reportedly limited to approximately 200,000 engines per year.^[1] On May 9, 2007, DMAX announced the production of the 1,000,000th Duramax V-8 Diesel Engine at its Moraine facility.^[1]

Contents 1 LG4 1.1 Specifications 2 LB7 2.1 Specifications 3 LLY 3.1 Specifications 4 LLY/LBZ 4.1 Specifications 5 LMM 5.1 Specifications 6 LMK 7 LGH 8 See also 9 References 10 External links

LG4

The LG4, or Isuzu 6H, is a commercial-grade vehicle engine and is currently operating in over 300,000 Isuzu and GM-built trucks, including the H-Series and T-series vehicles. It is mated to the Allison 3000 and 3500 Series transmissions.

The following trucks use the LG4:

• Chevrolet T-Series
• Isuzu F-Series
• Isuzu H-Series

Specifications

• Engine type: 7,785 cc (7.785 L; 475.1 cu in) I6 turbo
• Bore and stroke: 115 mm (4.53 in) x 125 mm (4.92 in)
• Block / Head: gray iron / cast iron
• Redline: 2400 rpm
• Aspiration: Turbocharged & Intercooled
• Valvetrain: OHC 4-V
• Compression: 16.0:1
• Common-rail
• Power / Torque:

Code	Years	Power@rpm	Torque@rpm
?	?	200 bhp (150 kW) @2200	520 lb·ft (705 N·m) @1450
?	?	275 bhp (205 kW) @2200	860 lb·ft (1,166 N·m) @1450
LYA	2009?-	215 bhp (160 kW) @2200	560 lb·ft (759 N·m) @1450
LYB	2009?-	230 bhp (170 kW) @2200	660 lb·ft (895 N·m) @1450
LYC	2009?-	260 bhp (190 kW) @2200	660 lb·ft (895 N·m) @1450
LYD	2009?-	260 bhp (190 kW) @2200	835 lb·ft (1,132 N·m) @1450
LQF	2009?-	300 bhp (220 kW) @2200	860 lb·ft (1,166 N·m) @1450

• Source: ^[2]

LB7

The LB7 (engine code "1") was first introduced in 2001 and continued until 2004. It is a 32-valve design with high-pressure common-rail direct injection and aluminum cylinder heads. The most problematic issue with the LB7 are injectors going bad. GM issued a warranty for this and currently injectors and warrantied for 7 years/200,000 miles. The Duramax was on the Ward's 10 Best Engines list in 2001 and 2002.

The following trucks use the LB7:

• Chevrolet Kodiak/GMC Topkick
• Chevrolet Silverado/GMC Sierra HD

Specifications

• Engine type: 6,599 cc (6.599 L; 402.7 cu in) V8 turbo
• Bore x Stroke: 4.06 in (103.1 mm) x 3.90 in (99.1 mm)
• Block / Head: Cast gray iron / Cast aluminum
• Aspiration: Turbocharged & Intercooled
• Valvetrain: OHV 4-V
• Compression: 17.5:1
• Injection: Direct; Bosch High Pressure Common-rail
• Power / Torque: 300 bhp (220 kW) @ 3100rpm / 520 lb·ft (705 N·m) @1800 rpm
• Source: ^[3]

LLY

The LLY (internally called the 8GF1) (engine code "2") is a 6,599 cc (6.599 L; 402.7 cu in) turbocharged engine which debuted in 2004 and continued until the end of 2005. It is a 32-valve design with high-pressure common-rail direct injection and aluminum cylinder heads. The LLY was GM's first attempt to implement emissions requirements on their diesel trucks. To meet this goal they turned to a newly developed Garrett turbocharger with a variable geometry vane system and they installed an Exhaust Gas Recirculation valve or (EGR Valve). Learning from problems with injectors in the previous LB7 GM changed the valve covers to allow access to the injectors without having to remove the valve covers, saving significant labor costs if injector replacement became necessary, and preventing leaked fuel from entering the crankcase, causing oil dilution. Early on problems came forward from customers complaining of severe overheating, and also in some situations blown head gaskets. Initially GM denied that it was a problem, but after it was sued by a consumer group it relented and included overheating and blown head gaskets as a warranted item.

The following trucks used the LLY engine:

• 2006 Hummer H1 Alpha
• Chevrolet Silverado/GMC Sierra HD

Specifications

• Engine type: 6,599 cc (6.599 L; 402.7 cu in) V8 turbo
• Bore x Stroke: 4.06 in (103.1 mm) x 3.90 in (99.1 mm)
• Block / Head: Cast gray iron / Cast aluminum
• Aspiration: Turbocharged & Intercooled
• Valvetrain: OHV 4-V
• Compression: 17.5:1
• Injection: Bosch High Pressure Common-rail
• Power / Torque: 310 bhp (230 kW) @3000rpm / 605 lb·ft (820 N·m) @1600 rpm
• Head casting is 8gf1
• Block casting is #22351021213
• Source: ^[4]

LLY/LBZ

The 2006 LLY (engine code "2") debuted in the beginning of 2006 and ended production with the start of the 2007 calendar year. Mechanically it is identical to the LBZ and is mated to the new 6 speed Allison transmission however it retained the LLY designation.

The LBZ (engine code "D") debuted in the earlier part of 2006 and continued into 2007 sold only in the "classic" body style. It has a more powerful tune loaded into the computer that allows it produce more power and torque.

Changes include:

• Cylinder block casting and machining changes strengthen the bottom of the cylinder bores to support increased power and torque
• Upgraded main bearing material increases durability
• Revised piston design helps lower compression ratio to 16.8:1 from 17.5:1
• Piston pin bore diameter increased for increased strength
• Connecting rod “ I ” section is thicker for increased strength
• Cylinder heads revised to accommodate lower compression and reduced cylinder firing pressure
• Maximum injection pressure increased from 23,000 psi (1,585.8 bar) to more than 26,000 psi (1,792.6 bar)
• Fuel delivered via higher-pressure pump, fuel rails, distribution lines and all-new, seven-hole fuel injectors
• Fuel injectors spray directly onto glow plugs, providing faster, better-quality starts and more complete cold-start combustion for reduced emissions
• Improved glow plugs heat up faster through an independent controller
• Revised variable-geometry turbocharger is aerodynamically more efficient to help deliver smooth and immediate response and lower emissions
• Air induction system re-tuned to enhance quietness
• EGR has larger cooler to bring more exhaust into the system
• First application of new, 32-bit E35 controller, which adjusts and compensates for the fuel flow to bolster efficiency and reduce emissions"

LBZ applications:

• Chevrolet Silverado HD
• Chevrolet Kodiak
• GMC Sierra HD
• GMC TopKick

LLY applications:

• Chevrolet Silverado HD
• Chevrolet Kodiak
• GMC Sierra HD
• Chevy Express full-size (reduced power output mated to a 4l80E transmission)
• GMC Savanna full-size (reduced power output mated to a 4l80E transmission)

Specifications

• Engine type: 6,599 cc (6.599 L; 402.7 cu in) V8 turbo
• Bore x Stroke: 4.06 in (103.1 mm) x 3.90 in (99.1 mm)
• Block / Head: Cast gray iron / Cast aluminum
• Aspiration: Turbocharged & Intercooled
• Valvetrain: OHV 4-V
• Compression: 16.8:1
• Injection: Bosch High Pressure Common-rail
• Power / Torque:

Code	Years	Power@rpm	Torque@rpm	Redline (rpm)
LBZ (Chevrolet Silverado 2500HD / 3500 Classic (auto trans), GMC Sierra 2500HD / 3500 Classic (auto trans))	2006-2007	360 bhp (270 kW) @3200	650 lb·ft (881 N·m) @1600	3450
LLY (Chevrolet Kodiak Medium Duty (LRX option), GMC TopKick Medium Duty (LRX option), Hummer H1 Alpha)	2006-2007	300 bhp (220 kW) @3000	520 lb·ft (705 N·m) @1600	3200
LLY (Chevrolet Kodiak Medium Duty (LPD option), GMC TopKick Medium Duty (LPD))	2006-2007	300 bhp (220 kW) @3000	605 lb·ft (820 N·m) @1600	3200
LLY (Chevrolet Express, GMC Savana)	2006-2007	250 bhp (190 kW) @3200	460 lb·ft (624 N·m) @1600	3450

• Source: ^[4]

LMM

The LMM engines are based on the LBZ engines, but it was designed for US EPA's 2007 emission standards, and uses ultra-low sulfur diesel fuel, which went on sale in the US and Canada in the fall of 2006.^[5]

New emission reduction features include Diesel Particulate Filter (DPF). The DPF traps particulate matter, and when the computer senses a pressure differential between two sensors (one located upstream and another downstream of the DPF) the truck enters a "regeneration" cycle. During this time the computer commands the fuel injectors to inject fuel after the cylinder has fired forcing raw fuel into the DOC (Diesel Oxidizing Catalyst) where the fuel is burned to elevate the temperature of the exhaust. This hot exhaust flows into the DPF and burns the trapped soot.

A version was used in Trident Iceni.^[6]

Specifications

• Engine type: 6,599 cc (6.599 L; 402.7 cu in) V8 turbo
• Bore x Stroke: 4.06 in (103.1 mm) x 3.90 in (99.1 mm)
• Block / Head: Cast gray iron / Cast aluminum
• Aspiration: Turbocharged & Intercooled
• Valvetrain: OHV 4-V
• Compression: 16.8:1
• Injection: Bosch High Pressure Common Rail with CP3.3 Injection Pump
• Power / Torque: 365 bhp (272 kW) @3200rpm / 660 lb·ft (895 N·m) @1600 rpm

Code	Years	Power@rpm	Torque@rpm	Redline (rpm)
LMM (Chevrolet Silverado HD, GMC Sierra HD)	2007-	365 bhp (272 kW) @3200	660 lb·ft (895 N·m) @1600	3450
LMM (Chevrolet Kodiak Medium Duty (LYE option), GMC TopKick Medium Duty (LYE option))	2007-	330 bhp (250 kW) @3000	620 lb·ft (841 N·m) @1600	3250
LMM (Chevrolet Kodiak Medium Duty (LRX option), GMC TopKick Medium Duty (LRX option))	2007-	300 bhp (220 kW) @3000	520 lb·ft (705 N·m) @1600	3250
LMM (Chevrolet Express, GMC Savana)	2007-	250 bhp (190 kW) @3200	460 lb·ft (624 N·m) @1600	3450

• Source: ^[7][8]

Emission controls:

• Additional combustion control, including an even more efficient variable-geometry turbocharging system, cooled (enhanced) exhaust gas recirculation (EGR) and closed crankcase ventilation to reduce nitrogen oxides (NOx)
• Additional exhaust control, including oxidizing catalyst and new diesel particulate filter (DPF) to reduce soot and particulate matter
• Increased-capacity cooling system
• New engine control software
• Use of low-ash engine oil (CJ-4)

Applications:

• 2007- Chevrolet Silverado HD^[9]
• 2007- GMC Sierra HD
• Chevrolet Kodiak
• GMC Topkick
• Chevrolet Express/GMC Savanna

LMK

General Motors plans a 4.5 litre 72-degree^[10] V8 for light-duty applications which will be built at GM's powertrain facility in Tonawanda, New York after 2009. Designed to fit in the same space as a Chevrolet Small-Block engine, it is expected to produce over 310 bhp (230 kW) and 520 lb·ft (705 N·m) of torque. It added urea injection, 29,000-psi (2,000 bar) piezo-electric common-rail fuel system over previous Duramax architecture.^[11]

It would initially be targeted for the Chevy Silverado/GMC Sierra and Hummer H2.^[12] Unlike previous Duramax engines, the 4.5 liter will be designed and built entirely by GM, without assistance from Isuzu.^[13]

As of March 2009, a GM spokesperson stated the engine project has been put on an "indefinite hold" due to current economic conditions.^[14]

LGH

It is a version of LMM engine, but updated to include improve rigidity and reduce noise, new 29,000 PSI piezo injectors, a complete system-hardening to tolerate 20-percent biodiesel mixtures, urea injection with 5.8-gallon urea tank. Vans and chassis-cab versions in Chevy Express and GMC Savana were rated 250 bhp (190 kW) and 500 lb·ft (678 N·m).^[15]

See also

• List of GM engines

References

External links

• GM Powertrain
• Duramax home page