Understanding Dyed Diesel and Its Uses

https://charlie-wiki.win/index.php/Understanding_Dyed_Diesel_and_Its_Uses

Dyed diesel is just regular diesel fuel that has been marked with a red dye to indicate it is not taxed for on-road use, making it legal only for off-road vehicles, farm equipment, and heating applications. This lower-cost fuel saves money for industries like agriculture and construction because it avoids highway taxes, but using it in a truck that drives on public roads can lead to hefty fines from inspectors who check fuel tanks for the telltale color.