Common Myths

Biodiesel affects how my engine operates.
Biodiesel blends of 20% or less show little to no change in an engines performance. In fact, engines are expected to experience less wear in the long run when using biodiesel. Many users of biodiesel blends notice significant reductions in soot. Also, carbon monoxide (CO), and hydrocarbon (HC) emissions outputs are reduced.

Biodiesel voids my warranty.
Federal law prohibits the voiding of a warranty solely because biodiesel was used—it must be the cause of the failure. All major auto and engine manufactures have affirmed that the use of high quality biodiesel blends up to B20 will not void their warranties. Original equipment manufactures (OEMs) positions on biodiesel blends and blend levels vary, and can be found on the National Biodiesel Board (NBB) site (

I need to modify my vehicle or engine to use biodiesel.
No vehicle modifications are necessary for blends of biodiesel as high as 20% biodiesel mixed with diesel fuel. Higher blend levels may require minor modification to seals, gaskets, and other parts, but only on older model diesel engines.

I cannot use biodiesel in a cold climate.
A biodiesel user’s experience with cold weather varies. B20 blends are used in some very cold climates such as northern Minnesota and Wyoming, where temperatures routinely fall below –30°F in the winter. As an example, B20 was used in an airport shuttle fleet for four years in Boston with no problems. Some users have reported using B100 in extremely cold climates such as in Yellowstone National Park. The vehicles were equipped with winterization packages and no other precautions were noted.