General Motors will introduce a new 4.5L V-8 Duramax turbo-diesel that improves engine fuel efficiency by 25% compared to gasoline engines, and reduces CO2 emissions by 13% and cuts particulates and NOx emissions by at least 90% compared to comparable diesels today. The engine will be rated in excess of 310 hp (231 kW) and 520 lb-ft (705 Nm) of torque.
This will be GM’s first engine to use a selective catalytic reduction NOx aftertreatment system with a diesel particulate filter to help achieve the Tier 2 Bin 5 and California LEV 2 emissions standards. The engine will be applied in pickup trucks of less than 8,600 lbs (3,900 kg) GVW and the HUMMER H2 after 2009.
This new GM light duty diesel is expected to become a favorite among customers who require excellent towing ability and fuel efficiency. It will meet the stringent 2010 emissions standards, and it will be compliant in all 50 states, making it one of the cleanest diesel vehicles ever produced.—Tom Stephens, group vice president, GM Global Powertrain and Quality
The new dual-overhead cam, four-valve V-8 diesel engine will fit within the same space of a small-block V-8 gasoline engine. This compact size is made possible by using integral cylinder head exhaust manifolds, integral cam cover intake manifolds and a narrow block.
Technical highlights of the engine include aluminum cylinder heads with integrated manifolding; a variable-vane turbocharger with intercooling; a Compacted Graphite Iron (CGI) block for a stronger and lighter engine base (compared to lower-strength aluminum or heavier grey cast iron); and fracture-split main bearing caps and connecting rods for a precise fit. An electronically controlled, ultra-high-pressure, common-rail fuel system is used, which has the ability to inject fuel five times per combustion event to control noise and emissions.
GM currently offers 17 diesel engine variants in 45 vehicle lines around the world. GM sells more than one million diesel engines annually, with products that offer a range of choices from the 1.3L four-cylinder diesel engine sold in the Opel Agila and Corsa, up to the 6.6L V-8 Duramax diesel sold in full-size vans, heavy duty pickups and medium duty trucks in the US.
GM first introduced the Duramax diesel 6.6L V-8 in the US in the 2001 model year.
GM will produce the new engine at its plant in Tonawanda, NY and is investing will invest $100 million in the plant for that purpose.