What Is Red Diesel Fuel, And What Happens If You Put It In Your Truck?

The last time you went to go fill up your car's tank with gasoline, you probably saw four options available at the pump for use: regular, mid-grade, premium, and diesel. This, of course, varies from pump to pump, but by and large, these are the gas options you can use to fill up your tank. One option you most certainly did not see at the pump was red diesel. This is diesel fuel that has been dyed red — the shade Solvent Red 26, to be precise. You may be wondering why a certain fuel would be dyed a particular color and may think it would be fun to have it in your vehicle. However, that is not going to happen, as it is against the law.

This is not because red diesel fuel is substantially more dangerous than your typical fuel, though it does contain a high amount of sulfur. Chemically, it is the same as the diesel fuel that you would get out of your average gas pump, and theoretically, any vehicle with diesel engine could use this red diesel fuel. It's not like having regular gasoline get into your diesel engine. However, red diesel fuel is specifically used for construction and agriculture vehicles, like bulldozers or cranes, for off-road use. The reason why the law allows those vehicles to utilize this red diesel but not your average commercial vehicle on the road is for one very specific reason: taxes.

Fuels for on-road and off-road use are taxed differently by the government. Off-road fuels, like red diesel, have a lower tax rate than your average gasoline precisely because of their commercial application and that these vehicles are not being used on the open road. The reason this fuel is dyed red is purely for indicating purposes. So, if you get pulled over and have your fuel tank inspected, they should not be finding any trace of red diesel in that tank, as then you would have clearly been trying to outsmart someone so you can pay less for fuel than you would for gas that has been taxed for on-road purposes.

The fines for finding red diesel — or any dyed fuel — in a commercial vehicle are quite immense. First off, if you refuse to have your vehicle inspected if you're suspected to have dyed fuel, you could be subject to a $1,000 fine. If red diesel is found in your gas tank, you will be fined either $10 per gallon or $1,000, depending on which amount is greater. Not only that, but you need to pay the tax that you skimped out on by going for this cheaper fuel option. Depending on what state your in, it could impose its own financial penalties as well.

Fuel prices are expensive enough. Do you really want to risk paying over $1,000 in order to drive across town? Leave the red diesel fuel to the construction workers and farmers.