General Motors has announced that its 2011 model year Duramax 6.6L turbo diesel engines will be fully compatible with a 20 percent blend of biodiesel (B20).

The move covers all 2011 GM heavy-duty products, including Chevrolet Silverado, GMC Sierra, Chevrolet Express, and GMC Savana.

“B20 capability in our new heavy-duty trucks is the latest addition to a growing number of alternate fuel options offered by General Motors,” said Mike Robinson, vice president, environment, energy and safety policy. “We are seeking different paths to fuel solutions in order to maximize efficiency, reduce emissions and minimize the dependence on petroleum.”

Previously, GM offered B20 capability as a special equipment option for fleets. GM announced several upgrades for 2011, such as upgraded seal and gasket materials, an upgraded fuel filter, and additional heating to the fuel circuit to make the new diesel vehicles B20 compatible with standard equipment.

“It’s a huge win for the biodiesel industry to have GM’s support for B20,” said Steve Howell, technical director for the National Biodiesel Board. “Over the past seven years, a tremendous amount of cooperative effort has taken place between the biodiesel industry and the auto and equipment manufacturers to secure broader support for B20 blends in their vehicles. From the development of stringent new ASTM specifications for blends up to B20, to intensified fuel quality enforcement efforts and emphasis on the BQ-9000 program, to sophisticated testing with new particulate and NOx aftertreatment technology – this has truly been a substantial team effort, and it’s finally paying off.”

The NBB and the National Renewable Energy Laboratory spent more than $10 million testing B20 during the last five years to ensure the fuel’s compatibility in new diesel engines and aftertreatment technology. Most of the NBB funding for the testing was provided by U.S. soybean farmers through the soybean checkoff program.

Chrysler was the first of the three major U.S. automakers to formally support B20 use by fleet customers in their Dodge Ram pickups starting in 2007, along with implementing B5 factory fills in the Dodge Ram and Jeep Liberty. This past fall, Ford announced that its model year 2011 Ford F-series Super Duty diesel pickup line will be fully approved for use with B20.

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