What oil filters do & What You Need to Know

They are small, disposable and inexpensive. We usually don’t give them much thought; into the recycle bin they go after every oil change. So, how important can that little oil filter be?

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What You Need to Know About Oil Filters

1. Change Your Oil Filter Routinely

Change your oil filter as part of a routine maintenance. The life and longevity of your engine depends greatly on its oil filter. Ignore it, leave it on too long, and you could be facing some very expensive repair bills. To avoid all that trouble, let’s spend a few minutes discussing the critical component that wields so much power over our engine’s life span.

2. What Does It Do?

As the name implies, it filters the engine oil. Why is that necessary? Because the inside of an engine is a dirty place. As fuel burns, it produces many harmful byproducts. Those are things like ash, chemical toxins, moisture, and worst of all, sludge. Sludge is that gooey, thick, messy substance you might see accumulating under the oil fill cap. If you left all those pollutants to circulate freely with the engine oil they would soon destroy expensive internal engine parts.

3. How Does It Work?

Engine oil contains detergent. High-quality oil contains better detergent, and more of it. That cleaning agent helps to prevent pollutants from sticking to internal engine parts. Instead, those harmful materials are held in suspension within the engine oil, where they are delivered, under high pressure and flow rate, to the oil filter.

The filter has a membrane material that traps and holds those foreign substances. High-quality oil filters have a finer membrane, and more of it, to do a better job of filtering under adverse conditions, like in extreme heat or cold, stop and go driving, or frequent short trips. Why are frequent short trips so bad?

Because a cold engine produces more harmful by-products of combustion than a hot engine does. Also, it doesn’t get hot enough, and doesn’t stay hot long enough to burn off some of those pollutants. That means more work for the oil filter.

Either way, the filter can’t hold an infinite amount of toxins. That’s why we replace the oil filter with every oil change. It’s a little amount to spend to protect the very expensive engine. It makes sense, right?

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