Can You Mix Synthetic Oil With Regular Oil?

August 11, 2022

Can You Mix Synthetic Oil With Regular Oil?

The short answer is yes, you can mix synthetic oil with regular oil. However, you should only use this combination as a temporary solution until you can receive a professional oil change. While mixing motor oils is safe, doing so will limit your oil’s performance. 

Mixing Motor Oil

Because most motor oils comprise a combination of additives and base oil, they’re typically compatible when mixed. However, synthetic and conventional oils have different refining processes, impacting their quality and performance. 

Synthetic oil is well-refined, meaning it contains higher-quality additives and minimal impurities, keeping your engine clean and lubricated for longer. Conventional motor oil is less refined than synthetic, resulting in increased residue buildup. Mixing these oils can dilute the synthetic oil’s beneficial properties by muddying it with less refined oil.


Synthetic vs. Conventional Oil

You can better understand why mixing synthetic and conventional oils is discouraged by knowing how each motor oil is formulated. 

Synthetic Oil

Synthetic motor oil comprises a petroleum-based base oil and evenly distributed high-quality powder additives. This mixture is designed to improve engine performance and protection for longer than other oils.

Due to its uniform properties, synthetic oil is highly effective across a wide temperature range, allowing for faster engine startups and longer running times between oil changes. Its low impurity levels allow for cleaner burning and slower thickening, reducing engine drag. Synthetic oil also produces fewer emissions by preventing gum and varnish buildup, promoting better fuel economy by reducing friction. 

Synthetic oils are ideal for older cars that don’t receive regular oil changes, as this oil can fend off contaminants and deposits, even when the vehicle isn’t in use.

Conventional Oil

Conventional motor oil comes from natural crude oil drilled from the earth. This oil is refined through sedimentation, which removes waste products and impurities. Finally, the oil is heated and vaporized, leaving a base oil that is combined with various fluids, such as detergents, anti-oxidants, rust inhibitors and dispersants. Which liquids are added to the base oil depend on the manufacturer. 

Regular oil is well-suited for newer vehicles used in light-duty applications and short-distance travel, as these tasks are less demanding for the engine.


Possible Negative Effects of Mixing Conventional and Synthetic Oil

Mixing synthetic oil with regular oil is safe but can have numerous disadvantages for your engine:

  • More frequent oil changes: Because conventional oil dilutes the beneficial qualities of synthetic oil, mixing them means you’ll need to get an oil change sooner. 
  • Reduced efficiency: Conventional and synthetic oils feature different additives, chemicals and detergents that can destabilize your oil when mixed, impacting your engine’s performance.
  • Lower value: Combining regular oil with synthetic oil lowers the value of your synthetic oil investment, meaning you won’t get the quality or performance you paid for.


Can You Use Regular Oil After Synthetic?

Switching to conventional oil after using synthetic oil in your vehicle is safe. Because both oils compromise compatible fluids, switching to regular motor oil is okay if your car has used synthetic before. Modern technologies ensure that these oils are similar enough in their properties that no complications will occur when mixed, despite synthetic oil having higher-quality ingredients.


Choose Motor Oil From Hot Shot’s Secret Today

You can ensure optimal engine performance and longevity with oil from Hot Shot’s Secret. We’re known for creating problem-specific solutions for the automotive, trucking, RV and agricultural industries designed to increase equipment efficiency and service life. Our products are backed by science and our money-back guarantee.

Contact us to learn more about our automotive products today!