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Synthetic vs. Conventional Oil: Differences & Benefits

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Synthetic vs conventional oilwhat’s the difference? 

While synthetic engine oil contains fewer impurities and provides better protection than conventional oil, both these engine lubricants have their benefits.

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

Fret not! 
In this article, we’ll discuss the major differences between synthetic and conventional oilhow they’re made, prices, and oil change intervals to help you understand each motor oil better.

This Article Contains

Let’s begin. 

Synthetic vs Conventional Oil: 4 Key Differences

Synthetic engine oil and conventional oil are used to lubricate engine parts
These oils also perform other functions like:

Despite similar functions, synthetic and conventional engine oils also have some key differences:

A. How They’re Made

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

1. 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. 

2. Conventional Oil 

Conventional oil is obtained by heating 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 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. 

B. 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 temperatures 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.

C. Pricing Differences

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

To give you an idea, synthetic motor oil can cost you about 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 that 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. This cheaper alternative to synthetic oil performs better than mineral oil. A synthetic blend also acts as a stepping stone when switching to synthetic motor oil.

D. Oil Change Interval 

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

1. 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: 

2. Conventional Oil 

Conventional oil, on the other hand, has a more frequent oil change interval compared to full synthetic and synthetic blend oil.

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 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.

Then, does this mean that synthetic oil is better than conventional oil?

Benefits of Synthetic vs Conventional Oil

While both conventional and synthetic oils have their advantages, synthetic oil outperforms regular oil in most cases.

Let’s take a closer look at the benefits each type of motor oil offers.

1. Benefits of Synthetic Oil

Synthetic oil is great for several functions, including engine protection at extreme temperatures. 

Here are some other benefits of synthetic motor oil:

Some potential synthetic motor oil disadvantages are:

2. Benefits of Conventional Oil 

Conventional motor oil may not be as refined as synthetic oil, but it still has a couple of advantages over the latter, like:

Here are the downsides of using traditional oil:

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

How to Pick the Right Engine Oil for Your Vehicle?

Choosing between synthetic and conventional oil isn’t as easy as you think. 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 habits 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: 

If you’re still confused, you can try another option — to alternate between synthetic and conventional oil. Or you can also try semi synthetic oil for your engine. 

Synthetic blend motor oil is cheaper than synthetic oil but performs much better than mineral oil. It also helps increase gas mileage and fuel economy. Plus, with proper maintenance, a synthetic blend can last almost as long as fully synthetic oil.

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

Closing Thoughts

Synthetic motor oil offers more advantages than conventional oil because of its synthetic additives and better viscosity. It‘s more effective in protecting your engine and provides far better performance for modern engines. 

Even so, it’s best to consult your owner’s handbook to choose the right oil for your vehicle. Also, 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!

With AutoNation Mobile Service, you can expect quality service at competitive and upfront prices from expert mechanics. Contact us today to get an oil change service, tire service, or any other repair done right in your driveway!