What is Red Dyed Ultra-Low Sulfur Diesel?

There is no difference between Ultra Low Sulfur Diesel (ULSD) and Red Ultra Low Sulfur Diesel (RULSD) except for the color. Red Ultra Low Sulfur Diesel simply has a red dye additive and is normally not available for purchase by the general public.  It is routinely used for off-road vehicles like farm equipment, heavy construction equipment, and generators.

Why use it?

Dyed Diesel is taxed at a lower rate than on road clear diesel. Why pay the extra taxes for clear diesel?