Switching to Synthetic Oil After 100k Miles: Pros and Cons

Switching to Synthetic Oil After 100k Miles

Synthetic Oil is a lubricant. This lubricant consists of artificially made -synthesized- chemical compounds. Otherwise known as Synthetic Lubricant, Synthetic Oil can be manufactured through petroleum components chemically modified rather than raw crude oil.

In other words, Synthetic Oil is created using a base oil combined with a series of additives. Crude Oil pumped from the ground is processed in a refinery to create a specially synthesized base oil.

As essential as it is that synthetic oil can be gotten from other raw materials too, the primary material remains distilled crude oil, which goes through modification- physically and chemically.

Synthetic Oil operates as a substitute where petroleum-refined oils work in extreme temperatures. Designed with improved lubricate properties and intensified thickness, Synthetic Oil provides enduring protection from engine wear.

Can You Switch to Synthetic Oil After 100K Miles?

Yes, you can switch to synthetic oil after 100k miles but ensure you are using the right velocity or a better range multigrade. Switching to synthetic oil would be of immense advantage when adhering to the manufacturer’s prescription.

Generally, Synthetic Oil is deemed to be an advancement of conventional oil. It is a mixture of synthetic and conventional base oils. Hence, switching to it is laced with more benefits than conventional oil.

Synthetic Blend Oil may suffix perfectly, particularly if the car has not been running fully Synthetic Oil from the beginning.

The Synthetic-Blend -or Semi-Synthetic Oil- is the meeting point of the Conventional and the Fully Synthetic.

This Synthetic Blend makes switching from conventional to fully synthetic easy for drivers- some solid middle ground for them.

However, there is a type of oil that helps reduce leaks; minimize oil consumption and smoke emission even in older engines.

The High Mileage Oil, as it is called, is precisely designed for cars with more than 75,000 miles. It contains friction additives, antioxidants, and detergent compounds; hence, for a journey of 100,000 miles already, the high mileage oil could be considered.

Why Do You Need to Switch to Synthetic Oil After 100k Miles?

Synthetic Oil is a detergent oil. It cleans sludge deposits, helps clean the engine, withstands extreme temperatures, and increases fuel economy. While at this, the car moves swiftly, navigating steeps and bends.

Synthetic Oil contains lesser impurities than Conventional Oils, thus increasing the overall quality performance and longevity of the engine. In more precise words, Synthetic Oil prevents the engine from wearing out without having lasted its lifespan.

That said, Synthetic Oil is of such friendliness to cars used in climates with hot summers or frigid winter seasons. Also, vehicles used for hauling or towing may be best filled with Synthetic Oil.

Older engines could enjoy a switch to Synthetic Oil, too. As some older machines are prone to sludge build-up, Synthetic oil help prevent it.

Will Switching to Synthetic Oil Cause Leaks?

No! Generally, switching to Synthetic Oil will not cause leaks. Actually, Synthetic Oil flows more efficiently for its thinner and lighter state than Conventional -regular- oil.

However, Synthetic Oil is more likely than Conventional oil to leak, where there is a part from where the oil could leak out the engine. But that the Oil itself would cause a leak? No.

Pros of Switching to Synthetic Oil After 100k Miles

To the extent of the longevity of a car’s engine, Synthetic Oil is effective, abiding with such ‘pros’ as:

1. Control of Extreme Temperature

A switch to Synthetic Oil helps regulate the car when it is too hot or cold. The Oil can be more resistant to degradation at high temperatures. It contains oil molecule sizes of a consistent size and ideal weight.

2. Prevention from Oxidation and Corrosion

A metal is said to be corrosive, where it can gradually destroy or is slowly destroyed by chemical or electrochemical reactions with its environment. Synthetic Oil helps to save the engine from this fate.

3. Long Service Life

The oil offers a long service life, affording the user the value for purchasing the automobile.

4. Minimal Sludge

Synthetic Oil minimizes sludge, sediments, stains, dust, debris, and blockages that may accumulate in the engine.

Cons of Switching to Synthetic Oil After 100k Miles

As appealing as the engagement of Synthetic Oil is, caution must be exercised in its application. This caution relates majorly to older vehicles, particularly with high mileage.

This is because the seal in older vehicles may not be able to manage the additives in synthetic oil. The oil, while cleaning out sludge, may remove deposits acting as seals.

Hence, other than synthetic motor oil, older vehicles- whose manufacture dates as far as 1990, have to use conventional motor oil.

In the light of the above, synthetic oil to older vehicles can result in:

1. Engine Leaks

This may be the most disturbing crisis any user would dare to face. Thus, avoiding it is more rewarding than managing its eventual occurrence.

2. Engine Damage

Aside from leaks, there are other damages that an automobile engine can suffer. Examples are: overheating, misfire, seal or gasket damage, or outright knock. In all, none of this, of course, would gladden the heart of any user.

However, it does not mean an older vehicle cannot wholly use synthetic oil. If the car is in excellent working condition and maintained over time, the oil may prolong its life and protect it. Wisely, a Professional Technician must be involved.

What Happens If You Put Synthetic Oil With Regular Oil?

Nothing outside that you dilute the beneficial effects of synthetic oil, which is of higher quality. Both are traceable to the same base oil source and, thus, contain the same agreeing components.

It may be safe to mix both, but you devalue your synthetic oil investment, and it may result in the need for an oil change earlier than expected.


In switching oil, the excitement of trying out something ‘new’ must be complemented by careful attention paid to the peculiarities and uniqueness of motor engines and body parts.

Ideally, the application of oil should generally obey the manufacturer’s instructions. And at the least, a professional input should herald every act of maintenance committed to your vehicle.