Rising fuel costs and concerns about dependence on foreign oil have led to a fuel race for researchers. One of the most promising technologies is biodiesel, a clean-burning fuel derived from vegetable oils instead of petroleum. Because it comes from renewable resources such as soybeans and corn, biodiesel tends to be less expensive than fuels from petroleum sources alone. The Environmental Protection Agency classifies biodiesel and biodiesel blends as advanced biofuels because they reduce emissions by as much as 87 percent over conventional petroleum-based fuels, so fueling your Ford-Powerstroke engine, GMC-Chevy Duramax truck or Dodge-Cummins motor with a biofuel blend could help keep the Treasure Valley area cleaner.

"Before you make the switch to biodiesel, though, it's important to distinguish between types of biodiesel and biodiesel blends", adds Gage Burlingame, Master Diesel Technician at Gem State Diesel in Meridian, Idaho. "Biofuel blends are labeled according to the content of biodiesel they contain along with conventional fuel. A B20 blend contains 20 percent biodiesel and 80 percent petroleum-based diesel; a B5 or B05 fuel is 95 percent petroleum diesel. A B100 fuel contains no petroleum products, but while you can convert vehicles to run on pure biodiesel as an agricultural diesel fuel, commercial diesel engines aren't designed to run exclusively on biofuel."

Full biodiesel conversion lets you run your diesel engine on B100 fuels, but check your owner's manual before taking this step. In most cases, converting to B100 biodiesel, reclaimed vegetable oil fuels or other fuels that aren't available at your corner station could void warranties on fuel lines, common rail injectors, fuel filtration systems and other key engine parts.

Biodiesel is more chemically active than petroleum-based fuels, and over time, high biodiesel percentages can cause additional wear on rubber fuel lines and gaskets. For newer trucks, the breakdown of rubber parts is less of an issue because newer materials are less reactive than their older counterparts. Commercial diesel engines run well on fuels of up to B20, and these biodiesel blends are widely available. For agricultural diesel equipment that may have a mix of older and newer diesel engine parts, ask a technician at diesel maintenance and repair shop like Gem State Diesel that can help you choose the right fuel mixture for your engine.

Blended fuels give you the performance of petroleum fuels with the cost-saving, green advantages of biodiesel. By itself, biodiesel is prone to gelling in colder weather. That may not matter in Miami, but for Boise diesel owners who need reliable performance even on cold winter days, it's a concern. In a B10 or B20 mix, gelling is rarely an issue. Pure biodiesel may also lower overall mileage, but biodiesel blends give you the same excellent mileage that makes diesel economical. If you haul heavy loads, you'll notice no difference in power between biodiesel blends and pure petroleum-based diesels.

Before you make the switch to a biofuel blend, give your truck, boat or agricultural equipment a thorough inspection. Biodiesel blends run clean and leave few deposits in your fuel system, but they can also dislodge pre-existing deposits. For the first few weeks of your engine's new diet, check and change filters frequently to trap and remove any detritus that gets scoured from fuel lines.

Technology may not let you swap to corn oil in your tank, but the newest biodiesel blends are a good way to economize.