What is Clear Ultra-Low Sulfur Diesel?

Ultra Low Sulfur Diesel (ULSD) is defined by the U.S. Environmental Protection Agency (EPA) as diesel fuel with a maximum sulfur content of 15 ppm. It is nearly clear in color and is mandated to be used in all on-road diesel vehicles.

Why use it?

Other than to meet EPA standards and taxation regulations there is no difference in engine performance between red dye ultra-low and clear ultra-low sulfur diesel. The dye in the fuel simply allows law enforcement to determine if it is being used as prescribed by law. Both clear and dyed diesel also meet ASTM D975 standards.