Can Dirty Oil Ruin Your Car Engine?

replacing dirty car engine oilYou should change your oil every 3,000 miles. Or should you? That’s a common figure you’ll see in news articles and informative posts.

But, it’s no longer the rule. The game has changed. From synthetic oils to new engines, your car may have very different oil change intervals.

And if you don’t know it, it could cost you. Changing your oil too late, or not at all, will lead to dirty oil.

Just how bad is dirty oil? And can dirty oil ruin your car engine? This guide will answer that question and more.

1. What Does Motor Oil Do?

Basic engine parts are always on the move. Oil plays a pivotal role in ensuring everything runs smoothly. As the cylinders pump, motor oil serves as lubrication to stop these metal components from grinding together.

But car oil has come a long way. It also serves a variety of other purposes.

Yes, it keeps heat under control by limiting friction in the engine. However, the oil itself also has special properties that rein in high temperatures. Plus, as the oil passes through the filter, it traps contaminants that would otherwise damage the engine.

2. How Does Oil Get Dirty?

Unfortunately, oil doesn’t last forever. The simple act of heating and cooling oil time and time again will cause it to degrade. Eventually, this will result in chemical changes that impact the effectiveness of the oil.

Most of the time, your vehicle’s oil system is closed. But this system itself is responsible for a degree of contaminants. Metal flakes from normal engine use will seep into the oil and get caught in the filter.

As fuel is converted to energy within the engine, it leaves behind a sludge-like residue. Oil does its job by washing this filth out of the cylinders. Of course, over time, this will dirty your oil.

The oil filter works in tandem with this circulating process, picking up these minor contaminants. But at a certain point, the oil filter becomes too clogged to snatch up particulates. These then remain in the oil.

Some manufacturers require you to change the oil filter every time you get an oil change. Others will ask you to replace it every other time. You should look at your car service manuals to see what’s best for your vehicle.

3. Can Dirty Oil Ruin an Engine?

There’s a reason you have to replace dirty engine oil so often. It can wreak havoc on any vehicle, especially when left unchecked for a long period of time. Since oil is the lifeblood of your car, your engine will pay the price when it becomes ineffective.

Eventually, the chemical changes and contaminants will impact oil’s special properties. Sludge will begin to build up in the cylinders as abrasive particles remain in the oil and wear the engine down. Your engine will suffer from a gradual reduction in lifespan until you perform an oil change.

But things get worse.

In the beginning, you might notice less gas mileage. Since contaminated oil isn’t very effective at managing heat, your engine will run far hotter than before. This could eventually lead to your vehicle overheating when you least expect it.

Allow this to happen for too long and dirty motor oil will ruin your engine. Once it loses its ability to lubricate the pumping cylinders, the metal parts will begin to grind together. This will destroy the engine and cause the vehicle to seize up as hot metal melds together.

Once this occurs, it’s already too late. You’ll be looking at a costly engine replacement.

4. How Do You Know You Need an Oil Change?

There are several myths about timing an oil change. They are almost all wrong.

One popular misconception states that you should change your oil once it’s turned dark. The reality is your oil is doing its job and picking up engine sludge. That doesn’t mean it’s time for an oil change.

Don’t rely on visible cues or strange tests to see if it’s time to change your oil. Always follow the recommendations found on your vehicle’s service manual. Manufacturers will recommend an oil change after a certain allotment of miles or a specific time interval.

When you reach one of these milestones, it’s time to change your oil. You can find online car manuals if you have misplaced yours or would like to read a digital copy in the comfort of your own home.

5. Should You Change Your Own Oil?

Every car owner should know some basic car maintenance tips so you have a choice when it comes to changing your oil. You can take it to an auto shop or do it on your own.

If you’re changing your own oil, be sure to follow the instructions located on your car manual. Some jurisdictions do not allow you to change your own oil for environmental reasons. It’s a good idea to check the area codes before doing it yourself.

Otherwise, take it to a shop of your choice. A bad oil change can cause a host of its own problems, so be sure to take it to a trustworthy mechanic.

Always Read the Car Manual

Whether you’re replacing dirty oil alone or at a shop, you need to know the contents of your car manual. These guidelines will ensure your car is always running its best. If you don’t know when to change the oil, you could drastically reduce the lifespan of your vehicle’s engine — or worse.

Don’t have the manual? You don’t have to look far. We have a large collection of free online car manuals, and they’re just a click away.