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Although sometimes considered more reliable than gasoline-powered engines, diesel engines must endure more wear and stress. As a result, it’s important to change diesel engine oil more often.



What is a Diesel Engine Oil?

The purpose of diesel engine oil is to protect and lubricate internal parts and to help ensure the engine does not overheat during typical operation. It is similar to oil used in a gasoline powered engine, but there are significant differences that make diesel oil unsuitable for use in the other types of engine.

How Does Diesel Engine Oil Work?

While it is made up primarily of a base oil blend, diesel oil has application-specific additives and proprietary differences based on the manufacturer. Diesel engine oil also has a much higher viscosity rate than its gasoline counterpart and features enhanced detergents, as diesel engines can create many toxic byproducts. Operationally, the engine oil is designed to circulate constantly and form a protective film between moving parts, so that they don’t come into contact with each other and cause failure.

How Is Diesel Engine Oil Made?

Oil for diesel engines originates from crude, which is sourced from deep wells in various locations around the world. It is composed of a base stock, to which different processes can be applied, such as solvent refining or hydra-processing. The lubricant itself makes up about three quarters of the product. As diesel engines can become especially contaminated by unburned fuel during the combustion process, engine oil must be manufactured with a high viscosity rate.

Why Does Diesel Engine Oil Fail?

  • An excess concentration of soot.
  • Water ingestion.
  • Owner’s failure to monitor or change.

What Are the Symptoms of Failure?

  • Poor performance.
  • Corrosion.
  • Low pressure.

What Are the Repercussions of Failure?

  • Premature rebuilds.
  • Complete engine failure.

If you have questions or concerns about engine oil or any of your vehicle’s components or fluids, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need.