Can you switch from synthetic blend to full synthetic oil

This article has been updated from its original 2015 version.

Q: Can conventional and synthetic oil be safely mixed?

A: With synthetic lubricants continuing to grow in popularity, the question of whether synthetics and conventional oils can be safely mixed often arises. Yes, you can safely mix synthetic and conventional oil. 

All motor oil, whether synthetic or conventional, is a combination of base oils and additives. Each are designed to be used in the same applications, so they each pass the same minimum standards. The main difference is conventional oil is typically designed to just barely meet standards while reducing the cost as much as possible.

Synthetics, on the other hand, usually surpass the minimum standards, and they typically contain higher-quality additives, too. In the end, conventional and synthetic oils are completely compatible. However while you can safely mix synthetic and conventional oils, you’re diluting the performance of the synthetic oil.  In fact many companies premix them, calling them synthetic blends, and sell them as a mid-grade performance product.

Information provided by: Amsoil

Synthetic blend vs full synthetic oil — what’s the difference? 

Both these lubricants have their benefits, but how do you choose the right oil for you?
Is synthetic oil better than synthetic blend oil?

This article will try to answer these questions and look at the benefits of synthetic blend vs full synthetic oils. We’ll also learn more about their manufacturing process, pricing, and oil change intervals. 

This Article Contains:

• Synthetic Blend Vs Full Synthetic Oil: What’s The Difference?
• Benefits Of Synthetic Blend Vs Full Synthetic Oil
• How To Pick The Right Oil For You?

Let’s get right into it!

Synthetic Blend Vs Full Synthetic Oil: What’s The Difference?

Synthetic oil and synthetic blend oil are both a type of motor oil used for the lubrication and protection of various engine parts against engine wear. These oils help prevent problems like engine wear, sludge formation, corrosion, and temperature control. 

Despite sharing some common ingredients, synthetic blend oil (semi synthetic oil) and synthetic oil are different. 

Here’s how they differ: 

How They’re Made

Synthetic blend oil includes synthetic base oil (fully synthetic oil) as one of its main ingredients. 

But they’re still very different in terms of how they’re made.
Let’s find out how:

1. Full Synthetic Oil

Full synthetic motor oil is entirely factory-made. It consists of a fully refined crude oil or refined petroleum as base oil. This base oil is obtained by modifying the base structure of the hydrocarbon atoms, thus preserving the best molecules in the process.

Synthetic oil is chemically created in the laboratory, which is why it can be very expensive. But it’s extremely high quality and great for superior performance.

2. Synthetic Blend Oil

On the other hand, synthetic blend oil is made from traditional oil (mineral oil) and synthetic motor oil as their base oil. Various synthetic and conventional mineral oils, additive compounds, and modifiers are then added to the mix.

The ratio of conventional motor oil and synthetic base stock oils in a synthetic blend can vary from brand to brand. Therefore, some semi synthetic oil blends might perform better than others. 

Pricing

Since synthetic blend oil is much easier to obtain, it tends to be cheaper than synthetic oil. It is, therefore, more economical and sustainable to maintain.

Due to the complex manufacturing process of full synthetic oil, it costs 30% more than any regular synthetic blend oil. It can also be expensive to maintain, especially considering how much more you’re paying per quart of motor oil.

But is synthetic oil worth the extra cost?

Oil Change Intervals

The length of your oil change interval is determined by the kind of engine oil you use for your car. 

While conventional motor oil (also known as regular oil) has a very short oil change interval, synthetic oil change and synthetic blend oil change vary in the following ways.

1. Full Synthetic Oil

Due to its highly refined nature and addition of synthetic additive compounds, synthetic oil performs far better than any other motor oil.

A synthetic oil change interval can go about 5,000 miles on the lower end without an oil change. And its best performance can take you anywhere from 10,000 to 15,000 miles before it needs changing.

2. Synthetic Blend Oil

On the other hand, a synthetic blend oil change can achieve an average of 6,000 miles. It performs far better than mineral oil but not as much as fully synthetic engine oil. 

Some synthetic blend motor oil brands may even guarantee 7,500 miles without a synthetic blend oil change. This is due to their ratio of conventional base oils to synthetic base oil. 

Both synthetic blend motor oil and fully synthetic oil have their advantages. And they both outperform traditional oil. 

But is one better than the other? 
In general, synthetic blend oil and fully synthetic oil are perfect for the following functions: 

• Keeping the engine clean so there are fewer impurities 
• Preventing sludge formation and protect against engine wear
• Protecting and lubricate engine parts against friction
• Protecting engine parts against water damage and corrosion 
• Keeping the engine cool and maintain its temperature 

Apart from serving these functions, synthetic blend motor oil and fully synthetic oil also have various other uses. Due to their unique properties, some are more suited for certain applications better than regular oil. 

Here are some benefits of synthetic blend vs full synthetic oil.

1. Benefits Of Synthetic Oil

Unlike conventional motor oil, synthetic engine oil is highly refined and contains fewer impurities. And even when compared to synthetic blend oil, it has many advantages that often make it a favorable choice, such as these:

• It offers longer oil change intervals than any conventional mineral oils or synthetic oil blend 
• It provides good fuel economy since you don’t have to change it very often, thus reducing the overall oil consumption 
• Since fully synthetic oil only contains synthetic additive compounds, the engine oil quality is more predictable than synthetic blend oil
• It prevents the formation of engine sludge and protects engine parts against damage from moisture 
• It has better engine performance and reduced friction that keeps the engine parts functioning like new for a long time

2. Benefits Of Synthetic Blend Oil

On the other hand, a synthetic oil blend achieves a middle ground between mineral oil and synthetic engine oil in terms of its performance and oil change interval. 

Compared to a conventional oil change, it provides a far better oil life. 
It also has the following benefits:

• It’s a lot cheaper than synthetic motor oil 
• Due to its more affordable cost, it’s sustainable to perform frequent oil changes and has better fuel economy
• It’s ideal for heavy-duty use (due to the addition of synthetic base oil) and is often recommended for light trucks and SUVs
• It has better protection against sludge, engine wear, and friction as compared to conventional oil made from crude oil
• It can withstand extreme temperatures without breaking down, unlike conventional oil

Considering these benefits, how do you decide which engine oil is the right pick for you? 
Let’s find out.

How To Pick The Right Oil For You

Generally, both synthetic oil and synthetic blend oil outperform traditional oil (conventional oil). But while choosing between the two, you need to consider your engine size, driving habits, and budget. 

If it’s an affordable choice for you, fully synthetic oil will do wonders for your car engine. However, synthetic blend oil is also a pretty good alternative to regular oil. 

Most car mechanics often rotate between a semi-synthetic and fully synthetic oil change. This helps them cut down on costs while still achieving high performance. 

You can also use a synthetic oil blend as a stepping stone towards completely switching to synthetic oil.

Keep in mind, you should look for the right type of oil that is best suited for your engine. For example, older engine vehicles that have reached a high mileage will require a high mileage oil. Some older engine models may even require the use of conventional mineral oils.

Most importantly, let your car manual decide the kind of oil your engine needs. Keep track of the various oil viscosity grade levels that these oils offer, and choose accordingly.

For example, viscosity grade 5W-30 is one of the most common you’ll find. 

Under this viscosity grade:

• The first number (5) denotes the oil viscosity at low temperatures 
• The second number (30) represents the viscosity at high temperatures. 
• The ‘W’ represents winter, i.e. the oil’s winter performance.

The lower the first number, and the higher the second number — the better. 

Closing Thoughts 

Both synthetic oil and synthetic oil blend offer several benefits as compared to regular oil. But remember to use the right kind of motor oil. 

Most importantly, get routine oil changes. 

Expired oil can cause many problems, including increased engine sludge, engine noise, exhaust smoke, and oil leak issues. Be sure to change your oil and get any oil leak fixed regularly. 

And if you need any help with your oil change services, contact RepairSmith!
RepairSmith is a mobile car repair and maintenance solution that offers competitive and upfront pricing and professional services from ASE-certified mechanics.

Fill out this online form to get an accurate cost estimate for an oil change service.

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