Can You Use Regular Oil after Synthetic?

Regular and synthetic oils are used to lubricate engine parts. This oil protects the moving parts of the engine, thus preventing wear and tear. Most people do not understand the differences between regular and synthetic oils, which lead to too many misconceptions. Most vehicle models today can use both regular and synthetic oil. One confusing question about the oil is can you use regular oil after synthetic? We will be answering this question in a while. We shall also learn more about regular and synthetic oil, their advantages and disadvantages.

Can You Use Regular Oil after Synthetic

What Is Synthetic Oil?

Synthetic oil is an artificially made lubricant made with man-made chemical compounds made by breaking and rebuilding petroleum molecules. This oil was first developed in 1929. It has since been used by almost all automobiles ranging from standard vehicles to high-performance cars to jets. This oil is made to substitute lubricant made from petroleum when working on extreme temperatures.

Synthetic oils offer superior chemical and mechanical properties compared to those in traditional mineral oils. It is the perfect choice for applications operating in extreme temperatures. The oils are made with chemically modified products like petroleum components, but its base material is distilled crude oil. The other additives to put in the oil and synthesis process depend on the producer, which brings the difference between different brands.

The level of addictive in synthetic oils is much less compared to conventional motor oil. They also feature fewer qualities of viscosity improvers due to the naturally high viscosity index (VI). A high viscosity index (VI) in synthetic oil means that it can retain its viscosity even when exposed to extreme temperatures. Synthetic oils are more expensive, but it is better in all aspects. This oil provides better engine protection, and you do not have to keep on changing.

Some of the measurable benefits of synthetic ail are oxidation resistance, low volatilities, and cold cranking properties. Oil oxidation determines the period it will be useful, and it can be measured using Turbine Oil Stability Test. Synthetic oils are better than Group I and Group II oils. The oil does not contain unstable hydrocarbons, sulfur, or other impurities. Synthetic oil is sturdy, and it does not produce harmful or hardy deposits.

The best way to get the right lubricant is by using viscosity grades. An engine oil grade has four characters, like 5W-40. The number with the W shows how the oil will flow when the weather is cold. The engine oil with a smaller first number has better flow when it is cold. For instance, when comparing 10W-30 and 5W-30, 5W30 flows easily at start-up temperatures compared to 10W-30.

The second number shows how the oil flows at the normal operating temperatures of the engine. 10W-30 flows easily than 10W-40 at normal operating temperatures. So when buying synthetic oil, consider one with high viscosity since it will protect your vehicle’s engine better.

Pros of Synthetic Oil

Outstanding Wear Protection: Engine components constantly contact each other when the vehicle is moving at high speeds, thus leading to friction. This friction between the parts makes them prone to break down and wear and tear.

Motor oils act as a protective barrier between the engine components. Synthetic oils retain wear and tear protection properties for a longer time compared to regular oils. This keeps the vital engine parts in good condition, thus increasing their useful life.

Stable Viscosity: Synthetic oils have a higher viscosity index making it stable in a wide range of temperatures. It means that the oil’s viscosity does not change much during engine start-up and different operating conditions.

Keeps the Engine Cleaner: The oil picks up deposits as it circulates through the engine. After some time, regular oils form sludge, which minimizes the engine’s efficiency, thus reducing its useful life. Synthetic oils resist the formation of deposits and sludge in engines because they are made with fewer impurities. If your engine already has sludge, the best synthetic oils will clean it after an oil change.

Optimized Fuel Consumption: Synthetic oils have a longer lifespan compared to regular oil. Synthetic oils should be recommendable changed at around 5000 to 7000 miles while some brands can eve 15000 to 25000 miles.

Better Turbocharger Protection: Most vehicles these days are made with turbochargers and smaller engines. Synthetic oils flow faster to the crucial parts, thus creating proper lubrication to the engine requirements. Full synthetic oils help to keep your turbocharged car to its maximum performance.

Cons of Synthetic Oil

Expensive: Synthetic oil is pricier compared to regular oil.

Not ideal for new vehicles:  New cars require the friction created when they use regular petroleum-based oils to work efficiently.

What Is Regular Oil?

Regular oil is also known as mineral oil or conventional oil. This oil works as a lubricant for automotive. These oils have been in like since 1908. It is made from petroleum, which is a natural substance. Today, regular oils are mixed using base oils made of polyinternal olefins (PIO), hydrocarbons, and polyalphaolefins (PAO), thus organic compounds comprising hydrogen and carbon purely.

One of the greatest advantages of regular oil is its inexpensive nature. Conventional oils need to be changed regularly since they have a short lifespan. If you remember to change the oil as required regularly, it will prevent the engine components from wear and tear.

Regular oils tend to break down much easily compared to synthetic oil. This makes the oil contaminated by forming sludge and deposits, which negatively affects the engine components. Sludge prevents the engine parts from moving properly, reducing engine performance, and shortening its useful life. Less sludge on the engine components also gives one better fuel economy.

The viscosity of conventional oils is not as stable as that of synthetic oil. These oils are very reactive to temperatures and thus are not ideal for operations with extremely low temperatures or very high temperatures. Regular oil should be changed every three months or 3000 miles or the one that comes first.

When choosing regular oil, check its viscosity grade. Check the vehicle manual on what the manufacturer recommends. The viscosity numbers show how well the oil will flow both at low temperatures and operating temperatures. Check the motor oil regularly, which will help you know when the oil needs to be changed or when it is running low.

Pros of Regular Oil

Inexpensive: Conventional or regular oil is the cheapest oil you will get for your automobiles. This oil can even be three times cheaper than synthetic oils.

Ideal for New Cars: Most manufacturers use regular oil during the assembly of the vehicle. Car owners are advised to continue using conventional oil when the vehicle is new. A new vehicle needs a break-in period of around 5000 miles. This oil from the manufacturer should be changed after six months or 6000 miles or the one that comes first.

Ideal for Old Vehicles: Regular oil is the ideal oil for old vehicles like those manufactured before 2000. Engines that have gone beyond their prime cannot utilize the benefits of synthetic oils, leaving conventional oils as the only choice.

Readily Available: Unlike synthetic oils, regular oils are quite easy to get in your nearby local shops. This means that whenever you need it, you will get it without too much hassle.

Cons of Regular Oil

Low Stability: When conventional oils are exposed to high temperatures, they become thinner. This, therefore, does not prevent engine parts from friction, thus leading to wear and tear.

More Break Down: Regular oil tends to break down more, thus leading to a shorter lifespan. Therefore, you must keep on changing to keep the engine parts well protected than using conventional oils.

More Impurities: Just like we have said above, regular oil breaks down fast, and this makes them prone to the building of sludge and deposits. When conventional oil breaks down, it sticks to different engine components forming sludge or deposits. These deposits eventually lead to damage to engine parts.

Cannot be used in Extreme Temperatures: Regular oil is not ideal for operations in high temperatures. This oil breaks down when exposed to extremely high temperatures, and lubrication is minimal when used in low temperatures.

Can You Use Regular Oil after Synthetic Oil?

Both synthetic and regular oil has the same application, and thus you can use regular oil after synthetic oil. People have had the misconception that when you start using synthetic oil, you cannot go back to regular oil, which is just but a myth. These two oil types are different, but not that much. Both regular and synthetic oils are made with lubricants to keep a vehicle’s engine performance steady and smooth.

You may ask yourself, what happens if you use regular oil instead of synthetic? Changing from synthetic oil to regular oil will not have any effect on the vehicle’s well-being. The only notable effect you will note is the change in engine performance. Synthetic is much better compared to regular oil in terms of quality. Therefore, you will note a change in the steady performance of the engine.

The fact that the engine’s performance decreases is what makes people think that changing from synthetic to regular is impossible. Experts recommend that you stick to synthetic oil instead of downgrading. This is because synthetic oil will keep your vehicle’s engine healthy and increase its useful life.

If you decide to change from synthetic oil to regular oil, there are several considerations you need to consider. It is recommendable to gradually change since you are introducing a completely new oil type to the engine. First, the switch from synthetic oil to semi-synthetic oil.

Switching from synthetic to semi-synthetic gets the engine to prepare for conventional oil. You can now introduce the regular oil completely later in the second phase. It is also recommendable to change the oil filter as you change the oil type.

It is vital to consider your car model when contemplating changing car oil from synthetic to regular. Newer vehicles have the upper hand when it comes to switching oil types. Old model vehicles may get some leakage problems when switching from one oil type to the other. It is, therefore, important to consult your vehicle manufacturer before you carry out the oil change.

Frequently Asked Questions (FAQs)

What Happens If You Use Regular Oil Instead Synthetic?

Using regular oil instead of synthetic oil may have some effects on the performance of your engine. Synthetic oils are of higher quality than regular oil, and it, therefore, improve the performance of your vehicle engine.

Regular oil is of low quality, and it does not offer good lubrication in extreme temperatures. It breaks down fast in higher temperatures, thus putting the engine parts at risk of wear and tear. It also breaks down to form sludge and deposits, which reduces engine performance.

In cold temperatures, regular oil takes time to heat up and get to the ideal viscosity. Therefore, if your car is recommended for synthetic oil, it is recommendable to stick to it to get the engine’s best performance.

Can You Use Synthetic Oil After Using Regular Oil?

Yes. It is possible to use synthetic oil after using regular oil. However, it is important to contact your car manufacturer on whether you can use synthetic oil on the engine. Moving from regular oil to synthetic oil is an upgrade.

You will experience a noticeable change in the performance of the engine. Synthetic oil makes the engine performance smoother and steady. You will also not need to keep on changing since it lasts longer.

Should I Use Synthetic Oil In My High Mileage Car?

You can use synthetic oil on high mileage vehicles, but again, it depends on the car manufacturer’s recommendations. A vehicle has high mileage when it goes beyond 75,000 miles. If the high mileage vehicle has been well maintained, synthetic oils will help to protect the engine and extend its useful life.

You can consider using some synthetic oils designed especially for high-mileage vehicles. When switching to synthetic oil in higher mileage vehicles, consult the manufacturer to get advice on the exact oil to use on the vehicle.

Is It a Good Idea To Put Synthetic Oil In Older Cars?

If you can use synthetic oil on older cars will depend on the car manufacturer. Some car manufacturers of older models recommend using regular oil, and changing it to synthetic oil may cause some Engine Problems, such as oil leakage. However, if the manufacturer allows you to use synthetic oils, it will be ideal.

Synthetic oil will enhance vehicle engine protection, thus increasing their useful life. Therefore, the right thing is to consult the vehicle manufacturer and clarify if you can use synthetic oil on your old car model.

Will Synthetic Oil Make Your Engine Last Longer?

Yes, synthetic oil is high-quality oil, and it makes your engine last longer. This oil has a stable viscosity and is thus ideal for high-temperature operations. Synthetic oils offer better lubrication, thus preventing wear and tear.

This improves the engine mileage making it last for a longer period. To get the best from synthetic oil, it is advisable to change it at least 6,000 miles. However, some synthetic oils can go up to 15,000 miles.

Final Words

By now, I am confident that I have answered the question; can you use regular oil after synthetic? Synthetic oil is more beneficial compared to regular oil since it has low viscosity, great lubrication, and a longer lifespan, among other pros. The oil is ideal for luxury car engines, towing and high loads, high-performance engines, and driving.

However, if you still want to switch from synthetic to regular, it is still possible. The difference you will note after the switch is decreased engine performance. Whichever oil you decide to use, remember to change it on time. This helps the vehicle to run efficiently and smoothly. It protects the engine from breaking down and reduces the number of times you go to the mechanic for maintenance and repair.

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Hi there, I am R. Hasan Tito, a mechanic, and owner of this website. My friend and I created this website to share our knowledge, expertise, and experience with our fellow mechanics' community and car users. I am a specialist and certified automotive mechanic (Both Heavy Commercial and Private Cars). I worked as a Mechanic and Mechanic Supervisor for over fifteen years at Global Rebound Automotive companies - Toyota, TATA, BMW, Nissan, TVs, and Others. Now, I enjoy my new role of leading a team of automotive experts (in their respective fields) and publish new content on a regular basis on my website and social media.

3 thoughts on “Can You Use Regular Oil after Synthetic?

  1. I hesitate to agree with you that conventional oil is low quality. Specifications are tough. A conventional formulation bearing an API rating of SP or an ILSAC rating of GF-6A meets the toughest new vehicle requirements. That would be a high quality lubricant.

    It’s true that lower quality oils are on the market, and should be avoided, such as economy oils bearing API ratings of SA or no ratings at all.

  2. hello mr. mechanic (Tito)
    I’m glad to find your website and very interesting to me… I just like making d.i.y. things to my vehicles… bec. I don’t want other mechanics touch my vehicles… (after the warranty period of the car)… if I can’t fix it…no other option but go to garanges with expert mechanics…and of course thru your tips on your website!

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