Clean vs Dirty Engine Oil: Everything You Need to Know!

It might be a case where you are wondering if it is the right time to change your engine oil. There is no doubt engine oil should be changed on a regar basis so that your engine may run smoother and it also helps to extend the lifespan of your vehicle.

As you can see, changing your engine oil frequently will provide you with a better performance while dirty oil may cause damage to your oil. So, it is always best to know the right time.

What Causes Engine to Get Dirty?

It’s safe to say that engine oil contains additives, anti-corrosive and lubricants that will ensure that your vehicle run as smoothly as possible. However, over a period of time, your oil will begin to lose its function and begins to collect dirt and debris.

Another thing is that the engine oil will likely face combustion as it plays its role in cooling down the engine, which usually happens as it collects heat. As soon as the engine oil begins to heat up, and the oil particles begins to break down into smaller parts.

There is no doubt that the decomposed products and environmental dirt and debris is what causes the oil to become dirty. It’s best to keep in mind that the engine oil gets dirty as it works to keep the engine clean.

It usually take 3 to 6 months for engine oil to get dirty which at this point it may cause harm to your engine. However, it has a lot to do with how you drive and where you drive to. So, if it’s a case where you spend most of your time in busy traffic, your oil may get dirty quicker.

Read Also: Engine Smoking After An Oil Change 

Clean vs Dirty Engine Oil: Symptoms

Clean vs Dirty Engine Oil

You may be wondering how to tell the difference between clean and dirty engine oil. We have a list of several ways to tell down below:

1. Viscosity

One thing you’ll find out is that dirty oil tend to have a higher viscosity when compared to clean oil.

You might be wondering wha t is viscosity? Viscosity has to do with how an oil is measured by its resistance to flow. When oil is thin it is said to have lower viscosity and pour more easily at low temperatures than thicker oils that have a higher viscosity.

What we recommend doing is to take a small amount of oil from your vehicle and test to see how well it flows to determine whether it is clean or dirty.

2. Impurities

It is said that dirty has contain lots of ash, metal particles, carbon residues, water and other contaminants. Another thing is that clean oil is known to be free of all impurities and is also composed of detergent and base oils.

3. Color

If you take a closer look at the color of your clean engine oil it will have a golden amber to reddish-brown appearance. However, it has a lot to do with the brand and type of oil you decide to use.

However, when oil is dirty it usually has dark brown or black color.

4. Texture

It’s best to keep in mind that dirty engine oil is dark, sludgy, and gritty when it comes to texture and this is cause by build-up of all the residues. While clean oil on the other hand is considered to be smooth, translucent and has a thin consistency.

Learn More: Why Does My Engine Oil Get Dirty So Fast

What Are the Signs That Your Engine Oil Needs Changing?

After six months of using conventional oil, you can expect to see a reduce in engine performance. If it’s a case where you don’t remember the last time you have change your engine oil or if your always caught up in busy traffic, then you may want to look out for these signs:

  • Poor fuel mileage
  • Dirty oil color
  • Lag in shifting gears
  • Engine warning lights
  • Engine overheating

How to Prevent Engine Oil From Getting Dirty?

Changing your engine oil on a regular basis is very important if you want to prevent your engine oil from getting dirty.

Here are some other tips you can follow going forwards:

  • Frequently Change Your Oil: The most effective way to prevent your engine oil from been dirty is to change it on a regular basis. Depending on the type of vehicle you have, you may need to change your oil every 3,000 to 5,000 miles. Another thing you can do is to check your owner’s manual to determine how often you should change the oil.
  • Use an Engine Sludge Remover: We highly recommend that you use an engine sludge remover since it helps to scrape off all the grit from your engine which will prevent your engine oils from rapidly declining.
  • Seek Help From Your Mechanic: We strongly believe that one if the best thing to do is seek help from your mechanic and if it’s a case where your oil needs to be change, you can let your mechanic do the job for you.


You should try your best to prevent your engine oil from becoming dirty since it can cost you a lot if you don’t change your oil at the right time. So, at any moment you notice a reduction in performance, weird oil color and viscosity, then these are signs your oil needs to be change. We highly recommend that you check your engine oil on a monthly basis.