John Baker
Can I Mix Synthetic and Conventional Oil?
Updated: Feb 22, 2022
Yes. There is no danger mixing synthetic and conventional motor oil. However, conventional oil will detract from the superior performance of synthetic oil and reduce its benefits. In this post, we’ll also look at if it’s safe to use regular oil after synthetic oil.
Let’s take a closer look.

Can I Mix Oil Types?
With synthetic lubricants continuing to grow in popularity, the question of whether synthetic and conventional oil can be safely mixed often arises.
I’m guilty of having mixed different types of motor oil with reckless abandon back in the day. A dash of synthetic-blend to top off my Buick Century one month and a shot of cheap conventional oil the next.
While oil performance probably suffered, my engine always remained in one piece.
That’s because you can safely mix synthetic and conventional oil. In fact, synthetic-blend motor oil is simply conventional and synthetic oil already mixed for you.
But, barring an emergency, it’s not a great idea to mix oil types.
