Chevrolet Trucks Blog

U.S. General Motors plans to use a new 4.5L V8 Duramax turbo-diesel powerplant for the Chevrolet Silverado, GMC Sierra half-ton pickups and the HUMMER H2. According to a press release, it will improve engine fuel efficiency by 25 percent, reduces CO2 emissions by 13 percent and cuts particulates and NOx emissions by at least 90 percent for North American light duty trucks and the HUMMER H2 built after 2009.

The new engine is expected to produce at least 310 horsepower and 520 ft-lbs. of torque. It also features dual-overhead cams, four valves per cylinder, a variable-vane turbocharger and aluminum cylinder heads with integrated manifolding that helps keep the overall package small enough to fit in the same space as the automaker’s small-block gas V8s.

“This new GM light duty diesel is expected to become a favorite among customers who require excellent towing ability and fuel efficiency,” said Tom Stephens, group vice president, GM Global Powertrain and Quality. “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.”

The environment will also benefit from this new V8 engine. It will have a 13 percent reduction in CO2 versus gasoline engines, and at least a 90 percent reduction in particulates and NOx compared to diesel vehicles today. 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 LEV 2 emissions standards.

“This new V-8 is not only a clean diesel meeting the toughest emissions requirements in North America, it also delivers an effortless performance feel because of its high torque across the speed range,” said Charlie Freese, executive director of GM Powertrain Diesel Engineering. “It is also significantly quieter than other diesels on the road today, with noise and vibration performance approaching gasoline V-8 levels.”

Freese said the new V-8’s compact size enables it to fit in the envelope of a gasoline small-block engine, which provides GM the flexibility to introduce this engine in a wide variety of vehicle applications should there be future market demand.

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. There will also use an electronically controlled, ultra-high-pressure, common-rail fuel system, which has the ability to inject fuel five times per combustion event to control noise and emissions.

GM first introduced the Duramax diesel 6.6L V-8 in the U.S. in the 2001 model year and since then, customer enthusiasm for this heavy duty diesel has been outstanding. In fact, GM’s heavy duty pickup truck market share has jumped nearly tenfold in the six years that Duramax engines have been offered.

This entry was posted on Wednesday, June 20th, 2007 at 3:51 am and is filed under Chevrolet Silverado, Chevrolet parts, Chevrolet news. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.