Is Synthetic Oil Bad For Older Cars?

Gone are the days when only high-performance cars used synthetic oil to achieve that extra oomph to reach the finish line first. Now synthetic oil is a popular alternative to conventional engine oil. Some manufacturers have even produced vehicle models that require synthetic oil for everyday driving.

However, not every car, truck, or SUV plying the road is the latest and greatest model year. Many of them are old machines that continue to run thanks to their owners’ tender care and considerable investment. Can these old cars safely switch from conventional oil to synthetic oil? And is there no going back from synthetic?

What Is Synthetic Oil?

Synthetic oil refers to lubricants that use artificially made chemical compounds. A process called synthesis breaks up petroleum molecules into its component carbons and hydrocarbons. These carbons and hydrocarbons are combined in a different way to synthesize new base oils.

You can divide synthetic oil into two types: Synthetic blend oil and full synthetic oil. While both use artificially created base oils, each type includes different chemicals for additional effects.

Synthetic blend oil combines both conventional and synthesized lubricants. These blends work better in cooling and greasing various engine parts. As a bonus, they cost less than all-synthetic formulas, making them much more attractive to budget-conscious drivers.

Full synthetic oil consists of artificially made lubricant plus additives that enhance the oil in various ways. One example is zinc, which helps reduce the chances of cylinder wash, a scenario where excess fuel carries away the oil that greases the cylinder walls.

Can You Put Synthetic Oil in Any Car?

Not every car will benefit from going from conventional oil to synthetic oil. Some vehicles are better off running on old-fashioned engine lubricant.

If you drive an older car that rolled out of the factory before 1990, you should refrain from immediately pouring synthetic oil into its engine. Otherwise, you might cause considerable problems for your vehicle.

Benefit and Disadvantages of Synthetic Oil

Early synthetic oils used esters as their base oil. Esters are artificial organic compounds made by reacting alcohol and carboxylic acids. They provide cooling and lubrication for various industrial and mechanical systems, such as air conditioners, refrigerators, and engines.

There are advantages to using ester-based synthetic oil. First, their stability ensures prolonged useful lives before you need to change them out.

Second, esters possess good solvency. They can dissolve contaminants that get inside the engine, which will slow down the accumulation of sludge.

Third, esters ensure excellent performance at both low and high temperatures. Whereas conventional oil becomes less effective in cold or hot weather, ester-based synthetic oils are less vulnerable to temperature changes.

Unfortunately, esters possessed drawbacks as well as advantages. While esters dissolve contaminants that could harm vital components, they also degrade the engine’s many oil seals. If one of those seals wore out, oil would leak out of the compromised part.

Furthermore, manufacturers designed the engines of older models to use conventional oil. Back in the heyday of old or classic cars, only high-performance vehicles like race cars and custom jobs used synthetic oil.

Synthetic Oil vs. Conventional Oil in Older Cars

Switching your old car from conventional oil to synthetic oil requires preparation. However, it’s usually worth the trouble if your vehicle can change to synthetic.

Synthetic oil offers several advantages over conventional oil:

• Improved lubrication of engine components
• Better at handling sudden changes in temperature
• Superior stability during cold temperatures
• Better at getting rid of debris and dust that got into the engine
• Specialized formulas for specific situations i.e. high mileage engines in old cars
• Lasts longer than conventional oil
• Lower volatility
• Responds better to additives

Also, the lower friction quality of synthetic oil results in higher fuel economy compared to the same viscosity mineral oil.

The main drawback of synthetic oil is its cost. Synthesizing base oils is more complex and expensive than refining regular oil.

Using Synthetic Oil in Your Old Car

If you want to switch your vehicle from conventional engine oil to synthetic oil, here are some things to keep in mind.

Ask the Manufacturer

No one knows a car like the company that designed and built it. So when you’re unsure about your old car’s compatibility with synthetic oil, always contact its manufacturer for recommended products.

Some car manufacturers developed synthetic oil products optimized for use in their older models. Try to get these in-house oil products as much as possible.

If you can’t find any synthetic oil developed by the manufacturer, scrutinize the product for certification that clears them for use in your old car.

Use Ester-Free Synthetic Oil

An ounce of prevention equals a pound of cure. Since esters cause issues for the engines of older vehicles, choose a synthetic oil product that doesn’t use these harmful chemicals.

Today’s synthetic oil products are ester-free. They use different compounds that don’t attack the engine seals. Synthetic oils also underwent thorough testing to ensure that they’ll protect your vehicle’s engine instead of damaging the oil seals.

To be safe, check the list of chemical compounds that comprise a synthetic oil product. If you see any mention of esters, drop the product and look for a different synthetic engine oil.

Flush Your Old Car’s Engine

You can add synthetic oil without draining the conventional oil from the engine. However, an engine flush can reduce the amount of accumulated sludge, which can make the switch easier.

Expect Oil Leaks

In some cases, the engine can leak after switching to synthetic oil. This can happen even though the new lubricant lacks esters that damage oil seals.

However, the problem doesn’t lie with changing the engine oil. And while the oil seals are at fault, they haven’t degraded.

Synthetic oil is thinner than conventional oil. While thinner lubricant flows better, it can also seep through small gaps that thicker engine oil usually can’t get through.

Inspect the oil seals to identify the part that developed a leak after changing from conventional to synthetic oil. You might need to replace the old seal with a tighter one to prevent the further loss of synthetic oil.

Myth: Why Can’t You Go Back to Regular Oil After Synthetic?

Actually, it’s possible to switch back to conventional oil. As long as the oil you switch to works with your engine, you can make the change as needed without any harm to your vehicle.

There are, however, some cases that have been recorded of vehicles developing oil leaks after switching oils one way or another.

How to Get Your Hands on Synthetic Oil

Most modern vehicles work incredibly well with synthetic oil. If yours does and you’re considering investing in it, you can expect a lot of benefits, such as improved stability and better performance. The tricky part, however, is finding the best oil to use for your vehicle. Fortunately, you won’t run out of options when you shop at CarParts.com.

Our website makes it easy for car owners like you to find the right oil for your ride. Use our search filters to find the motor oils with your preferred brand and price. Place your order and check out in minutes. You can also dial our toll-free hotline for further assistance.

Here at CarParts.com, you’ll never go over budget while shopping for your automotive needs. All our motor oils are available at competitive prices to help you get the best value for your money. On top of that, our warehouses are strategically located all over the US, meaning you can get your new oil in as fast as two business days.

Check out our catalog and shop now!