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Tractor Fuel vs Reefer Fuel: What’s the Difference?

Tractor fuel and reefer fuel can both be used in trucks and heavy equipment. However, there is one key difference: reefer fuel cannot be used on vehicles that will ever be driven on public roads. 

However, there is one notable exception. Refrigerated trailers, also called reefer trailers, are driven on-road. However, the reefer fuel is not used to power the truck. It is only used to maintain the refrigeration. 

Here’s everything you need to know about tractor fuel vs reefer fuel, so you can avoid making costly mistakes.  

What Is Tractor Fuel?

Tractor fuel is a type of diesel adapted to local climate conditions. In the early and mid-20th century, tractor fuel was a type of low-grade diesel similar to kerosene. Now, it is also called number two diesel and is somewhere between gasoline and diesel in the distillation of crude oil. 

Tractors, trucks, semis, and many construction vehicles can use tractor fuel. Vehicles using tractor fuel can be driven on public roads. However, it is more expensive than reefer fuel as it is subject to road tax. 

But how much is tractor fuel? That varies based on state road taxes, but as of June 2022, it is about $5.57 per gallon.

What Is Reefer Fuel?

Reefer fuel is a special type of diesel only allowed in off-road vehicles. This diesel is dyed red to clearly distinguish it from standard diesel. Because vehicles that use reefer fuel do not use highways or public roads, it is not subject to road tax.

This makes it a cost-effective solution for farm or construction vehicles that operate on private property. Reefer fuel can also be used in refrigerated trucks to maintain temperature – but not to power the truck itself.  

That’s because if the trucks are driven on the road, the company could face fines. If a vehicle using reefer fuel is caught even crossing a public road the driver can be fined up to $10,000 or more in some states. 

Tractor Fuel vs Reefer Fuel

Which fuel should you choose? That depends on the vehicle you’re using and its intended purpose.


Reefer fuel can be used to maintain the temperature in refrigerated trucks, commonly called reefer trucks. However, it cannot be used to fuel the truck on the road. 

Reefer fuel can also be used in agricultural or farm equipment that will never be driven on a public road. For example, on large development projects or farms work vehicles can use reefer fuel. 

Tractor fuel, in contrast, is also a standard number 2 diesel. But tractor fuel can be used in any vehicle that takes diesel. There are no penalties for driving vehicles with tractor fuel on public roads. 

For vehicle type, there are just two questions to ask. First, can the vehicle take standard number 2 diesel? And second, will it need to ever drive on a public road? If the answer to both is “yes,” then tractor fuel is the best choice. 

Cost & Usage

The major reason to choose reefer fuel instead of tractor fuel is to save on cost per gallon. Without road tax added, reefer fuel’s price is lower everywhere, especially in states like California with high road taxes. 

Reefer fuel costs about $2.97 to $2.99 per gallon as of June 2022. The retail price of standard number two diesel, by contrast, is now $5.57 per gallon

According to the U.S. Department of Energy, an idling truck burns about 0.8 gallons of diesel per hour. Trucks burn an average of 1,500 gallons of fuel while idling per year. 

Over the course of a year, off road vehicles could save an average of $3,870 by using reefer fuel. And that is just idle time! If you use 3,000 gallons of fuel a year, that is a savings of $7,740 per year, as long as the vehicle doesn’t drive on a road. 

Characteristics of Fuel

Keep in mind that it is easy for government officials to see when it is used on the road. The bright red dye makes it stand out. 

Officials use a black light to detect die residue in the fuel tank or major engine parts. The cost of being caught can be up to $10,000 in some states, which should seriously deter you from taking the risk. It is not worth doing so.  


As most people know, normal fuel is taxed by the government. These taxes are used for road maintenance, rest stops, and other services provided by the Federal Highway Administration. 

Both gasoline or diesel are taxed for all types of vehicles. However, since reefer fuel is an off road diesel it is not taxed. If you try to use vehicles with reefer fuel on the road, you will be fined for illegally using these vehicles  on the road and evading road taxes.  

Know Your Fuel Purpose

What is tractor fuel vs reefer fuel? In summary, they are similar on a chemical level, and they can be used in the same types of vehicles, though they serve different purposes. Reefer fuel can only be used in off-road vehicles or for the purpose of maintaining refrigeration in reefer trailers. Tractor fuel can be used in any vehicle that can take standard number two diesel. All in all, it’s important to understand how they’re different so that you don’t accidentally use one when you should opt for the other! .


Is reefer fuel the same as diesel?

Chemically, reefer fuel is similar to diesel. However, it is not the same as diesel because it can only be used on private property. It is dyed red to prevent misuse or confusion in its intended purpose. It can be used to maintain refrigeration in reefer vehicles – but not to power the truck.

Can you run off-road diesel in a reefer trailer?

You can use off-road diesel or reefer fuel in a reefer trailer, as long as the fuel is not used to propel the vehicle on the road. Reefer fuel or low emission diesel are often used to maintain temperature controls in reefer trailers. 

How long does reefer fuel last?

Reefer fuel used to maintain refrigeration in a reefer trailer usually lasts three to five days. How long the fuel lasts will depend on the climate, how often the trailer is opened, and the size of the fuel tank. 

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