Distillate fuel oil: (click here) A general classification for one of the petroleum fractions produced in conventional distillation operations. It includes diesel fuels and fuel oils.
Products known as No. 1, No. 2, and No. 4 diesel fuel are used in on-highway diesel engines, such as those in trucks and automobiles, as well as off-highway engines, such as those in railroad locomotives and agricultural machinery.
Products known as No. 1, No. 2, and No. 4 fuel oils are used primarily for space heating and electric power generation....
This is a graph of the use of the distillate. The primary use is a highway fuel.