Chevrolet and GMC today announced details of General Motors\' bi-fuel 2013 Chevrolet Silverado and GMC Sierra 2500 HD extended cab pickup trucks. Fleet and retail consumers can place orders beginning this April. The vehicles include a compressed natural gas (CNG) capable Vortec 6.0L V8 engine that seamlessly transitions between CNG and gasoline fuel systems. Combined, the trucks offer a range of more than 650 miles. The Silverado and Sierra will be available in standard and long box, with either two- or four-wheel drive. \"The bi-fuel Chevy Silverado and GMC Sierra provide customers with choices in advanced propulsion technology, and because CNG is a clean-burning, domestically produced fuel, it has wide appeal, \"said Ed Peper, general manager, GM Fleet and Commercial Operations. \"The addition of a full-size bi-fuel pickup truck to GM’s fleet portfolio is another milestone in putting the customer first in everything we do — by offering great products, innovative solutions and a great customer experience.\" The bi-fuel trucks are built with a specially designed engine, the fuel system is installed by GM\'s Tier One supplier and the completed vehicle is delivered directly to the customer. This process makes ordering the bi-fuel option as seamless and efficient as a standard vehicle.