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What Are the Risks of Switching to Synthetic Oil in Older Cars?

Oil bottle

If you've heard about the benefits of synthetic motor oil in vehicles, you may be ready to switch. This type of oil offers many advantages over petroleum-based motor oil, which appeals to drivers and car owners. The most important advantage is that it extends the life of your engine better than regular oil. However, there are some risks you should be aware of if you own an older vehicle.

What is synthetic oil?

First, you should understand the difference between synthetic oil and regular oil. Regular oil is made from crude oil and refined through a special process. Synthetic oil is made from other raw materials and may or may not contain some petroleum products, depending on the manufacturer. It's created through a man-made process instead of being refined from crude oil.

Synthetic oil offers several advantages of regular oil. It's less susceptible to temperature changes and does a better job of protecting the various components in the engine. It also provides more stability in cold temperatures and is more effective at cleaning out dust and debris from the engine.

Is synthetic oil safe?

In the past, warnings were given about switching to synthetic oil because it could harm the engine. The reason for this warning was that many synthetic oils were made of esters, which are organic compounds mixed with alcohol. This combination was often hard on the seals in the engine system and would cause them to wear down and result in leaks.

The way synthetic oils are made has changed over the years, and today they are as safe in vehicles as regular oil. In fact, your vehicle won’t even notice the difference if you maintain the same weight of oil regardless of whether it is petroleum-based or synthetic.

The one exception is for its use in older vehicles, especially those with high mileage. However, that doesn’t mean you can't ever switch if you have an older car.

Using synthetic oils in older models

When using the term “older” to refer to cars, it means those manufactured before 1990 or so. The risk with these models is that the seals and other components often aren’t as tight as with newer models. The synthetic oil could leak out and the vehicle could burn or lose oil. What this means for you is that you would be replacing your oil and having to monitor the levels more often. If you didn’t, you would risk damaging the engine or other components. Because synthetic oil does a better job of cleaning out sludge, it could remove deposits that are acting as seals.

It’s not accurate to say that you should never use a synthetic oil in an older car. If the car has been maintained and is in excellent running condition, the synthetic oil may protect the vehicle and prolong its life.

Signs of problems with synthetic oil in older cars

If you decide to switch to synthetic oil for your older car, talk to a professional mechanic first. He may want to check over your vehicle before advising you. If you make the switch to synthetic oil on your own, you will notice oil leaking out from the vehicle if there is a problem. You will need to have a mechanic look at it and make any necessary repairs or replacements. It's important to read the owner’s manual or talk to a mechanic about any changes you want to make with the type of oil you are using to protect your older model vehicle and ensure its long life and continued performance.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
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