|Bi-fuel Chevrolet Silverado. Click to enlarge.
General Motors is introducing compressed natural gas (CNG) bi-fuel versions of the 2013 Chevrolet Silverado and GMC Sierra 2500 HD extended cab pickup trucks. Fleet and retail consumers can place orders beginning this April.
The vehicles feature a CNG-capable Vortec 6.0L V8 engine that seamlessly transitions between CNG and gasoline fuel systems. With both CNG and gasoline tanks full, 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 Vortec engine features hardened exhaust valves and hardened intake and exhaust valve seats. Bosch supplies the fuel injection system. The trucks use a 17-gallon Type 3 CNG tank made from composite material with aluminum liner and carbon fiber wrap. GM placed a collar around the head of the tank for further safety.
|Fuel tank and fuel door. Click to enlarge.
GM mounts the tank through the bed of the truck to the frame; the fuel door is high up and out of the impact area. All of the high pressure fuel lines run inside of the frame rails.
The trucks always start on gasoline, then switch over automatically to CNG after a few minutes once the appropriate temperature is reached. The trucks continue operating on CNG until the CNG tank is depleted, and then it automatically switches back to gasoline. The driver can switch from CNG to gasoline using a switch on the dashboard. An LED system on the switch monitors the fuel in the CNG tank.
Horsepower and torque are identical to the base truck when running on gasoline. On CNG there is “minimal” loss of horsepower and torque, according to GM. The bo-fuel truck offers comparable towing capability. The CNG system adds 450 lb. to the total weight of the truck.
GM is the only manufacturer to offer a single-source option for its gaseous fuel vehicles. The bi-fuel trucks are built with a specially designed engine, the fuel system is installed by GM’s Tier One supplier (IMPCO) 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.
The bi-fuel commercial trucks will be covered by GM’s three-year, 36,000-mile new vehicle limited warranty and five-year, 100,000-mile limited powertrain warranty and vehicle emissions warranty, meeting all Environmental Protection Agency (EPA) and California Air Resources Board (CARB) emission certification requirements.