The two main types of diesel fuel are standard diesel fuel and biodiesel. Standard diesel fuel, derived from petroleum, comes in different grades, with Diesel #2 recommended for typical driving. Biodiesel is obtained from plant oils.
Diesel fuel, or diesel oil, is derived from petroleum, just like gasoline. However, it is safer because it does not ignite as easily, and also more efficient because it generates more energy per gallon. This type of diesel comes in two grades: Diesel #1, or 1-D, and Diesel #2, or 2-D. While Diesel #2 is used for most engines, Diesel #1 flows better at cold temperatures.
Biodiesel is derived from agricultural products, such as rapeseed oil and soybean oil. While blends containing up to 30 percent biodiesel can be used in diesel engines, only those with 5 percent biodiesel and 95 percent diesel oil can be used without voiding manufacturer warranties in the United States.