Synthetic Oil Or Conventional Oil: Which Is Better For Engines?

Published on 06/29/2022

synthetic oil or conventional oil which is better for engines

When it comes to choosing synthetic oil or conventional oil the number of drivers who opt for synthetic or semi-synthetic motor oil changes increases every year. Conventional motor oil is still an option, and for older vehicles or vehicles with heavy mileage, conventional oil may be the better choice.

What Is Right For Your Engine, Synthetic Oil Or Conventional Oil?

Learning about the facts and benefits of different oil types and whether synthetic oil or conventional oil is best for your vehicle.

Conventional Motor Oil

Conventional oil originates from crude: the “original” engine lubricant because that is all there was until the 1990s. Its main advantage today is a lower cost compared to synthetic oil. Conventional oil remains the preferred option for older cars manufactured when conventional oil service was the only option. 

Mileage is another key factor when debating synthetic oil or conventional oil. Cars with 75,000 miles or more benefit from conventional oil. When a car racks up tens of thousands of miles, its gears and moving parts suffer substantial wear and tear. Conventional oil flows more slowly than its synthetic counterpart, providing better lubrication to older, worn engines.

The main downside of a conventional oil is that extreme temperature fluctuations can cause the oil to degrade, leading to clogs and residual deposits.

Synthetic Motor Oil

Like conventional oil, synthetic oil originates from crude oil. Synthetic oil combines crude oil with additives to chemically synthesize a petroleum product that functions similarly to conventional motor oil.

Semi-Synthetic Motor Oil

Semi-synthetic oil (also known as synthetic blend oil) combines synthetic and conventional oil to provide better lubrication and engine protection than conventional oil alone. Because semi-synthetic oil falls between synthetic and conventional motor oil on the petroleum product spectrum, it offers some of the benefits of fully synthetic oil at a lower price point.

It is crucial to know that no industry regulations mandate a minimum percentage of synthetic attributes to classify as a synthetic blend. To learn more about the composition of synthetic-blend motor oil, visit the manufacturer’s website and look for the product’s data information sheet.

Two key values to look at include:

  •         Viscosity Index: Synthetic blends with a high viscosity rating indicate that the oil consists of an optimal base ratio of synthetic oil that provides substantial lubrication and protection while remaining stable at extreme temperatures.
  •         Pour Point: This is a measurement of the oil’s ability to remain fluid at cold temperatures—the lower the number, the better the synthetic base oil ratio.

What Are The Advantages Of Synthetic Oil?

According to AAA (American Automobile Association), synthetic oil and synthetic blend perform better than conventional oil across several indicators.

Benefits of synthetic oil over conventional oil include:

Improved engine protection

Conventional oil causes sludge to build up over time, compromising engine performance and shortening its lifespan. The additives in semi-synthetic and synthetic oil have lubricating properties that better protect the engine from rust, corrosion, and general wear and tear. Switching your motor oil from conventional to synthetic oil will also prevent engine sludge.

Synthetic motor oil is also effective in protecting diesel engines. Check out our dedicated blog post to learn more about diesel engine oil change.

Better performance in extreme temperatures

Conventional oil thickens in cold temperatures, making it move more slowly. Slow-moving motor oil leaves vital engine parts temporarily unprotected when you start your car, whereas synthetic oil flows easily and quickly, even in cold temperatures.

Synthetic oil also outperforms conventional oil in extreme heat conditions. Turning off an engine while still hot can lead to turbo coking: conventional oil cooks inside the turbo, causing a buildup of deposits that destroys the turbo. Synthetic oil, on the other hand, does not evaporate or break down at high temperatures and offers superior heat resistance for hot-running engines.

Maximizes fuel economy

Conventional oil settles and thickens in the cold and degrades until hot temperatures, making it less energy efficient than synthetic oil. In comparison, synthetics flow freely at start-up, maximizing fuel economy.

Extends oil change intervals

Synthetic motor oil outlasts conventional oil because of its superior stability. The specific time and mileage intervals depend on your operating conditions and the quality of the oil.

While synthetics mostly outperform conventional oil, actual results vary from brand to brand, and some synthetic brands will last longer than others.

Most synthetic oils last between 8,000 and 10,000 miles, while some brands allow for drain intervals as high as 25,000 miles. 

For best practices, follow the oil-change instructions provided in the owner’s manual of your vehicle or on the label of your motor oil.

When Is Conventional Oil Preferable To Synthetic Oil?

Fully synthetic motor oil is the preferred option for most vehicles because it prolongs the life of your engine and reduces the frequency of oil changes. However, the best oil for your car depends on your specific vehicle and driving habits. The age of your vehicle, its engine type, and the amount of mileage accrued will should determine the best motor oil for your needs.

For an older engine with high mileage, synthetic oil compounds can compromise the seals, resulting in engine leaks.

Synthetic motor oil surpasses conventional oil on almost every benchmark. It provides outstanding protection from wear and tear, chemical breakdown, and harmful deposits.

When deciding on what type of oil is best for your vehicle, be sure to review the manufacturer’s recommendations in your car’s manual. If you are still unsure whether to use synthetic oil or conventional oil, consult a licensed professional for guidance.

Contact Us For Diesel Engine Service

Our team of automotive experts at All Bay Diesel professional is ready to assist with prompt, professional, mobile repair services in Berkeley, CA, and the surrounding areas. From brakes services to oil changes and transmission repairs for your diesel engine or other heavy equipment, we have everything you need to get you back on the road.

When you need Berkeley mobile truck repair, call All Bay Diesel at 925-522-1780. Our mobile service team comes to wherever you need us in the San Francisco Bay area.

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