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What are the Different Types of Diesel Fuel?

by Shelley Moore

Any fuel used in a diesel engine is called diesel fuel. These fuels are classified as 1D, 2D and 4D. A main difference between these is the pour point, the lowest temperature a liquid will flow. A second difference is viscosity, the resistance of a liquid to flowing. Most diesel fuels are made of petroleum, but other types are available such as biodiesel and synthetic diesel.

4D Usage

4D fuels are only used in very low-speed engines such as those in stationary units or marine operations.

Cold Weather

1D diesel fuel has lower viscosity and a lower pour point than 2D, so is preferred for cold weather.

1D Considerations

1D diesel fuel has only about 95 percent of the energy output as 2D, causing reduced gas mileage and lower horsepower.

2D Fuel

2D fuel is used in warmer weather, and also can be mixed with 1D for an effective winter fuel.


Another type of diesel fuel is biodiesel, obtained from vegetable oil or animal fats. Some versions can be mixed with petroleum diesel.

Synthetic Diesel

Synthetic diesel fuel is derived from various sources such as wood, straw, corn and even garbage and food scraps.

About the Author

Shelley Moore is a journalist and award-winning short-story writer. She specializes in writing about personal development, health, careers and personal finance. Moore has been published in "Family Circle" magazine and the "Milwaukee Sentinel" newspaper, along with numerous other national and regional magazines, daily and weekly newspapers and corporate publications. She has a Bachelor of Science in psychology.

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