Can You Mix Fully Synthetic With Semi Synthetic Oil?

Can you mix fully synthetic with semi-synthetic oil? In a quick Google search, you can find that many people say that yes, you can mix synthetic and semi-synthetic oils. However, the majority of people recommend using fully synthetic oil if it is going to be used for engines with high mileage.

This post will explore the differences between synthetics and semis as well as their pros and cons for your engine.

Fully Synthetic Oil & Semi-Synthetic Oil: The Pros & Cons

	Pros	Cons
Fully Synthetic Oil	1. Superior lubrication capabilities for your engine 2. Stay cooler at higher temperatures 3. Higher resistance to wear on critical engine parts 4. Can be used in high-temperature diesel engines, including diesel on airplanes, trains, and trucks 5. Consistency of performance 6. Longer lifespan	1. A little bit more expensive than semis 2. Can’t be used in hybrid engines 3. Possible incompatibility with some of today’s antifreeze and additives
Semi-Synthetic Oil	1. High mileage oil 2. Can be used in older engines designed for mineral-based oil (ex: older Ford, Chevy, etc.) 3. Less expensive than fully synthetic oil 4. Resistance to wear on components that are not prone to wear	1. Does not perform as well as fully synthetic oil 2. Does not stay as cool at high temperatures3. Not compatible with all engine types, such as hybrid engines and diesel 4. Some added friction and heat that is not found in fully synthetic oils

 

Fully Synthetic Oil Vs Semi-Synthetic

The main difference between synthetic and semi-synthetic oils is in detergents. Semi-synthetics will typically contain much less detergent than synthetics, so they only go so far when cleaning your engine. If you use a semi-synthetic oil in your engine, it will need to be changed out much more often than if you were using a full synthetic.

If you are looking at price, there can also be a big difference. Full synthetics are usually quite expensive, while many semi-synthetic oils are much cheaper.

Fully Synthetic Oil Vs Semi-Synthetic Oil For Your Engine

Fully synthetic oils are recommended if you have high mileage on your vehicle. Because they have more detergents than semi-synthetic, they will be able to clean better. If you have used a semi-synthetic for your car and it is now at high mileage, you should switch to a fully synthetic one.

However, if you are looking for cheaper oil, a semi-synthetic is the way to go. But remember that it won’t be as good at cleaning as a full synthetic. Overall, it is safe to say that full synthetics should be used for engines with high mileage and semi-synthetic oils should be used at lower mileage. Of course, there are many other factors that you should consider when choosing an oil, so please read more below.

Can You Mix Fully Synthetic With Semi-Synthetic Oil?

Absolutely! There is no problem mixing them together. However, you will want to change the oil more often if you mix the two different types of oils together. So like the title says, yes you can mix the two oils together. If you want to be on the safe side, just use fully synthetic oil and you will be fine.

Final Words

You can mix the two oils together if you want, but you will need to change the oil more frequently depending on your specific engine. Is better to use a fully synthetic oil than mixing semi-synthetic with fully synthetic oil. You should use full synthetic oil in your vehicle if it has over 75K miles on it or if it is high maintenance.