Sulfur in Diesel: ULSD, Biodiesel and More

Sulfur is a staple in all diesel products available, but what does it mean for you? Is it good for your vehicle? Let’s take a look at the different levels of sulfur in diesel products and how it affects your equipment.

What is Ultra-Low Sulfur Diesel?

Since 2010, U.S. regulations require all pumps to dispense ultra-low sulfur diesel (ULSD) instead of low- sulfur diesel (LSD). Along with this, all vehicles made after 2007 are only compatible with ULSD due to the reduced sulfur content. ULSD contains 97% less sulfur compared to LSD, which makes the diesel safe to use with newer emission control mechanisms in modern vehicles. Higher sulfur content is harmful to these systems. Sulfur is not only bad for engines, but also is one of the leading pollutants in diesel exhaust.


Is Biodiesel Ultra-Low Sulfur?

Biodiesel is a fuel made from plant or animal products and results in less pollution than traditional diesel. It must meet the same ULSD standard for total sulfur to comply with EPA regulations. Therefore, biodiesel generally it contains even less sulfur than ultra-low sulfur diesel. While there are small differences between biodiesel and traditional diesel, they do not pose a danger to your engine when you go to the pump. In Oregon, all diesel sold at the pump is at least 5 percent biodiesel (also known as B5).

Is Off-Road Diesel Ultra-Low Sulfur?

Off-road diesel, or dyed diesel, is also ultra-low sulfur. It still complies with the EPA environmental requirements and will not damage engines. However, do not fuel your highway vehicles with it, as it can only be used with equipment that will not be driven on public roads. This equipment can include generators, construction equipment or other diesel-powered machines. To learn more about off-road diesel, check out our blog about clear and red-dyed diesel.

If you still have questions about what diesel products are right for your vehicles, reach out to our staff at 800-523-0600 or and they’ll be happy to answer any further questions you have.