What Are the Risks of Using Oil Additives in Your Car?

Today’s vehicles are not the same as they were even twenty years ago. With all the technological advances, car manufacturers are creating engines that are much more powerful and complicated than ever before.
And these engines need components and fluids that can keep up with the demands of these newer engines. This includes everything from coolants to oil.

That’s why today more than ever, people are turning to oil additives in order to boost the effectiveness of their car’s engine oil. Even people that go the extra and buy synthetic oils often supplement them with additives.

And even though using them can greatly enhance some of the natural properties of many types of oils, they aren’t without risks when used for the wrong applications or not adhering to the manufacturer’s instructions.

So we wanted to write this article so that you can clearly understand not just some of the types and benefits of using these chemical compounds, but what risks are also involved when you use them incorrectly.

Types of Oil Additives

You can find a ton of different types of oil additives on the shelves of any auto parts store. The choices can frankly be quite dizzying! So it is important to know at leat the basics of what each type of additive is and what their proper applications are.

Friction Modifiers: All combustible engines that require fuel create friction due to the internal moving parts. Friction modifiers work by coating the parts so less friction is created and the engine doesn’t need as much fuel to power for the same mileage.

Viscosity Index Improvers: The viscosity Index refers to how well a liquid does when it’s heated or cooled as far as its consistency. As oil heats up or cools off, its thickness (viscosity) changes and begins to thin out too much in higher temperatures, and thickens too much during colder temperatures thus lowering how well the oil is coating the moving parts in your engine. Viscosity improvers help keep your oil at the correct thickness regardless of the temperatures of the oil.

Anti-Wear Additives: These types of additives are specifically formulated to generate a chemical reaction that makes small particles in the additive stick to any metal parts of the internal engine. This in turn gives you a chemically sealed barrier to help keep wear and tear caused by friction within the motor to a minimum.

Detergents and Dispersants: The detergents found in oil additives work like any other detergent, they clean your engine from the inside. The dispersant compounds work in conjunction by keeping anything the detergents clean off suspended in the oil so that all the contaminants are flushed out during your normal routine oil change and are no longer trapped in the crankcase.

Usually when you buy an oil additive for your car, you’ll notice it doesn’t just do one thing. Oil additives are often stacked with additives in such a way as to improve a few different problems at the same time. It’s up to you to know which ones you need, and which you don’t.

Risks of Using Oil Additives

Obviously there are a lot of benefits in using the correct oil additives for your car. But that doesn’t mean any additive is beneficial and should just be willy nilly dumped down your oil spout. There are definitely some risks to clearly know as well. Here are the most common ones:

Damaging Engine Components: Especially on older cars that have cracked seals and gaskets, some of the stronger oil additives can eat away at these and cause more problems than they are solving. In fact, some additives can even corrode old parts and cause premature engine failure when used incorrectly.

Clogging Oil Passages: Sometimes when you’re cleaning out your engine’s oil system for the first time, especially with older cars, you could end up with clogged oil passages as the gunk that has been stuck to your engine’s interior begins to freely flow throughout the system. This is why it’s important that for older cars, if you are going to use a detergent in your additive, it should also include a dispersant to make sure the cleaned condiments don’t get a chance to get stuck somewhere else.

Causing Excessive Wear: Of course one of the reasons you even want to use an oil additive is to minimize wear and tear, but using too much or the wrong type for your specific car and driving environment can do just that. So know which additive you need and why, or ask your mechanic for some help if you’re still unsure.

Disrupting Oil Flow: Some of the oil additives you can buy are actually quite thick. Thick enough that if you use enough of them and they’re not meant for the conditions in which they were designed for can easily disrupt the flow of your oil which can cause a lot of problems.

Voiding Manufacturer’s Warranty: This is a very serious issue as some car manufacturers do not want you to use any oil additives as they didn’t design their engines to work with them. So if it is stated in your warranty and you use them anyway, you can completely void your warranty leaving you open to all repairs after.

Contaminating Oil: Sometimes if you’re using the wrong additive with the wrong oil, like a synthetic oil and a non-synthetic oil compatible oil, you can actually contaminate the synthetic oil and cause it to break down far faster than was originally designed leaving your engine exposed to all sorts of problems.

Misleading Oil Analysis Results: If you have something like a race car or high performance engine where you test the oil’s health, additives can often skew the test results leaving you with information that isn’t accurate.

The easiest way for you not to succumb to these types of risks is to know exactly what oil you are using in your car, the type of oil additive you feel you need and why you need it, and be sure that your warranty isn’t at risk!

Common Myths about Oil Additives

Even though these products have been on the shelves for a very long period of time, there are still a lot of misconceptions when it comes to using oil additives. Here are a few of the more popular ones.

Myth 1: All oil additives are good for all cars.

This sadly isn’t the case at all and a lot of people end up dumping additives their car doesn’t need or isn’t designed for their specific driving habits, often causing a lot more harm than good. These are additives meant to increase an oil performance, not a magic substance that can fix all of your car’s problems overnight. You need to be realistic on what an additive can do for you and to what degree.

Myth 2:Oil additives can fix existing engine problems.

Again, while oil additives can potentially help ease some problems or even prolong an engine’s life a bit, they can not fix a broken head gasket or decrease engine wear that already exists. Sometimes they can ease a certain problem, or at least the obvious signs of a problem, but it doesn’t mean the additive has fixed the underlying core problems.

Myth 3: Oil additives are necessary for newer engines.

This myth has a lot more to do with the way the engine was manufactured, the quality of oil you are using in your new car, and the fine print in your warranty. Many new cars are sold with high quality synthetic oils that already contain some of the substances found in over the counter oil additives. So by adding even more, you’re actually just wasting your money, and possibly causing damage and voiding your car’s warranty.

The only thing that can really guarantee your car is running the way it should is to have it checked out regularly by a certified mechanic, and to always perform the normal scheduled routine maintenance laid out in your owner’s manual.


Overall, oil additives can definitely have their place and are totally worth the additional cost of using them. But that doesn’t mean you don’t need to be sure on what it is you need and why you’re using them.

As long as you understand the risks and rewards involved and the proper use of whichever additives you are choosing, you should be okay and the additives should be helping your engine rather than hurting it.


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