Posted & filed under England Carrier Services.

Dirty diesel. What is it? Why should you care? Dirty diesel fuel is fuel that has built up sludge, slime, grime, and is likely not fit for use. Diesel fuel that has been sitting in storage tanks for long periods of time without proper testing or treatment starts to go bad. This is the stuff you don’t want to run in your truck. Dirty diesel often results in clogged filters and deposits in fuel injectors. Eventually, these become reduced vehicle performance. What causes dirty diesel fuel?


The Big Three: Dirty Diesel Contributors

Time, weather, and microorganisms are three primary contributors for diesel going bad. Diesel fuel has a normal shelf life of 6-12 months when no outside environmental factors are affecting it. Extreme weather can make the shelf life much shorter. Weather, condensation and water leakage happen when warm moisture comes in contact with cold diesel or a cold tank. Mother Nature’s mood swings create heat and humidity that have a definite effect on fuel energy. Warmer temperatures already degrade diesel without humidity. Finally, the bugs that feed on the hydrocarbons in diesel eventually die. Their bodies become contaminants in the diesel fuel running in your vehicle.


Other Diesel Contaminants

There are other contaminants to be aware of when considering diesel. Lead, sulfur, and certain other additives will contribute to engine issues.  We already know lead is toxic to humans, but catalytic converters will also sustain permanent damage if exposed to lead. Though sulfur naturally occurs in fuel, the fuel refining process can leave too much sulfur in the mixture. When this happens, damage occurs in converts, clog filters, and traps. Naturally most drivers turn to additives and special treatments to remove the additional sulfur. However, some additives contain metal that causes ash to build up in engines and will clog them anyway.


How to Avoid Dirty Diesel Fuel

Know your diesel fuel provider, know your fuel and know your “cetane number.” The cetane number for diesel is like the octane rating for gasoline. However opposite in meaning. A high cetane number means the fuel ignites faster, producing a longer, cleaner fuel burn than diesel with a lower cetane number.  Research shows that a cetane number of 50 or over is best for OTR trucks.

An awareness of what influences diesel fuel quality is invaluable to the carrier that fuels up frequently. Preventing dirty diesel by being mindful of what kind of fuel you put in your truck, and how long the fuel stays there, will save you substantial time and money.



The England Carrier Services (ECS) division offers a variety of services for carriers ranging from maintenance to support. As ECS members, carriers have access to nationwide discounts on fuel and tires from dedicated team members who are committed to finding the best price. ECS also provides factoring services with benefits such as same-day funding to a bank account or fuel card. These options allow carriers the freedom to focus on growing their business while saving time and money.