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Synthetic vs Conventional Oil: Which Is Better For Your Engine?

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Synthetic vs conventional oil: Curious about what sets these motor oils apart?

While synthetic oil boasts purity and protection, don’t count conventional oil out yet — each has its own perks.

So which one’s better?
how do you choose the right oil?

Fret not!
In this article, we’ll discuss if synthetic oil works better than conventional oil to keep your engine running smoothly and the major differences between the two. We’ll also explore how they’re made, the price difference, and their ideal oil change intervals.

Let’s hit the road!

This Article Contains: 

Is Synthetic Oil Better than Conventional Oil? (Advantages and Disadvantages)

Typically, synthetic oil offers several advantages over conventional oil (also called mineral oil). However, if it’s better for your car depends on several factors like your vehicle age, driving style, and your budget. 

Let’s break down the pros and cons of each oil type.

A. Synthetic Motor Oil

In general, synthetic oil fairs better than conventional mineral oil by offering: 

But some potential disadvantages of synthetic motor oil are:

B. Conventional Motor Oil

On the other hand, conventional motor oil may not be as refined as synthetic oil, but it still has a couple of advantages over synthetic.

However, the downsides of using traditional oil are:

Now that you know the advantages and disadvantages of each type of oil, let’s dig a little deeper into their differences to understand these oils better. 

Synthetic vs Conventional Oil: 4 Key Differences

Synthetic engine oil and conventional oil are used to lubricate engine parts, slow down corrosion, prevent engine sludge, and transmit engine torque for maximized horsepower. 

But, despite similar functions, synthetic and conventional engine oils have some key differences.

1. How They’re Made

Both synthetic and conventional engine oils are made from refined crude oil, but each process’s quality and complexity vary greatly: 

A. Synthetic Oil 

Synthetic oil is chemically produced in the laboratory by refining crude oil to get a synthetic base oil — to which various additives are added, like castor waxes and paraffinic oils.

The base oil is synthesized by rearranging hydrocarbon molecules. These synthetic base oil molecules are uniform in shape with fewer impurities between them — resulting in a highly reliable motor oil with improved stability to the oil’s structure under higher temperatures and pressures. 

B. Conventional Oil 

Conventional mineral oil is obtained by heating refined crude oil at various high-temperature points — leaving behind a heavier base oil. This acts as the base for conventional motor oil. 

Certain additives are then added to this base oil for increased performance and engine protection. Although conventional oil protects against friction and engine wear, it’s less refined than synthetic oil. 

2. Oil Viscosity Index

The viscosity index (VI) for conventional oil is 95-100, whereas, for synthetic oil, it’s above 120. 

Synthetics have a naturally higher VI than conventional oil because of their additives. The higher viscosity of synthetic oil makes it capable of withstanding extreme cold or hot temperature conditions and pressures without getting affected. 

But this doesn’t mean all synthetic oils work for all temperatures. If you’ve noticed, every motor oil bottle has an American Petroleum Institute (API) label printed on it. This label explains the viscosity and performance index of the oils.

3. Pricing Differences

Conventional motor oil (mineral oil) is much cheaper than fully synthetic oil. 

To give you an idea, synthetic motor oil can cost two to four times more than conventional oil. For example, five quarts of conventional oil cost about $28, while the same amount of synthetic oil is around $45.

That’s because producing synthetic engine oil is costlier than other motor oil types, as synthetic oil requires advanced technology and equipment. This means it can also be expensive to maintain a regular synthetic oil change schedule. 

As a result, most people often shift to synthetic blend motor oil (or semi-synthetic oil) — a combination of fully synthetic and conventional oil. Synthetic blend motor oils also act as a stepping stone when switching to synthetic motor oil.

4. Oil Change Interval 

An oil change is crucial to maintaining engine performance. Let’s see how the two oils differ in this aspect:

A. Synthetic Oil 

While synthetic oil does cost more, it also has a longer oil change interval

Most vehicle mechanics and manufacturer manuals recommend getting a synthetic oil change every 5,000-7,000 miles. However, it can go as long as 10,000 to 15,000 miles if you follow good driving practices like: 

B. Conventional Oil 

Conventional oil, on the other hand, has a more frequent oil change interval compared to full synthetic and synthetic blend oil. This is because conventional oil is more prone to oxidation and degradation.

You can expect about 3,000-5,000 miles from your traditional oil. In best-case scenarios, it can go for about 7,000 miles without needing an oil change service.

Once your mileage exceeds the regular oil change interval, you’ll start experiencing signs of bad motor oil. If you notice dark, muddy oil with suspended impurities, you may have expired oil.

So, how do you choose the right motor oil for your car? 

How Do I Pick the Right Engine Oil for My Vehicle?

Choosing between synthetic oil vs conventional oil isn’t as straightforward as it may seem. There are some essential aspects that you need to consider.

Let’s see what they are.

1. Synthetic oil 

Most modern engines, especially turbocharged engines, come equipped with synthetic oil. 
If your car originally uses conventional oil, you can swap it out for synthetic. But whether it’ll work or not depends on your driving style and conditions.

You can choose synthetic motor oil:

2. Conventional oil

Although a car with an older engine is more suitable for conventional oil, switching to synthetic is also possible. 

But sometimes, switching to synthetic oil isn’t the best option. 
For instance: 

Whether you choose a conventional or synthetic motor oil type, remember to refer to your vehicle’s owner manual to ensure it’s safe for your car

With the basics out of the way, let’s address any additional doubts. 

3 FAQs on Motor Oils

Check out the answers to some common questions vehicle owners have about motor oils. 

1. What’s the Difference Between a Full Synthetic Oil and a Synthetic Blend?

Here’s what each means: 

In essence, fully synthetic motor oil offers top-notch performance, while synthetic blend oil balances performance with affordability. Your choice depends on your priorities and budget.

2. What is Multi-Grade Oil? 

Multi-grade oil is also known as multi-viscosity engine oil. This oil flows well at low temperatures while still protecting your car’s engine at high temperatures. It’s identified by two numbers separated by a “W,” indicating its viscosity at cold temperatures (e.g., 5W) and high temperatures (e.g., 30.) 

It achieves this versatility through viscosity index improvers (VIIs) — additives that adjust the oil’s viscosity based on temperature. 

Multi-grade oil provides better protection, improved fuel economy, and simplifies maintenance by eliminating the need for seasonal oil changes.

3. Does Synthetic Engine Oil Improve Mileage?

Synthetic oils can improve mileage to some extent by improving your car’s engine efficiency rather than affecting fuel consumption directly. 

Here’s how: 
Synthetic oils have a smoother molecular structure that helps reduce friction between engine parts, optimizing engine operation and contributing to better mileage over time. 

However, the impact on mileage also depends on vehicle condition, driving habits, and engine maintenance

Keep Your Vehicle Engine in Top Shape with the Right Oil Type

Synthetic motor oil offers more advantages than conventional oil because of its synthetic additives and better viscosity. It‘s more effective in protecting your vehicle’s engine and provides superior performance for modern engines. But don’t forget to get routine car maintenance to keep your vehicle in good shape and optimize fuel economy. 

And if you’re looking for a mobile auto repair maintenance and service provider, look no further than AutoNation Mobile Service!

Whether you drive a Toyota sedan or a Chrysler SUV, with us, you can expect quality automotive service and a 12-month | 12,000-mile warranty on all repairs. 
Contact us to get an oil change service, brake repair, tire service, or any other auto repair done right in your driveway!