Does oil help with noisy engines?

Nobody likes a noisy engine, and if you have one, you’re probably on the lookout for an easy fix for it. In truth, there are lots of potential causes for engine noise. One thing that drivers look to is the engine oil. Can motor oil or engine oil additives make an engine run quieter? The answer is, it depends.

It Depends On The Cause

It depends on what the real cause of the noisy engine is. In considering whether motor oil can quiet that noisy engine, think about what the proper function of motor oil is. Motor oil functions to lubricate moving parts and protect them from wear damage caused by metal-to-metal contact and movement. Motor oil also protects lubricated surfaces by cleaning damaging deposits and removing them from those surfaces. Motor oil neutralizes corrosive acids that form in the heat and pressure of the engine environment. And lastly, motor oil serves an important function of dispersing and moving heat away from engine parts.

Whether motor oil can lessen engine noise depends on whether the cause(s) of the noise are tied to any of those oil functions. The most obvious possibility would be the first one – metal-on-metal contact. Yet if engine noise is related to this, it’s most likely because you’re low on oil to begin with so there’s not enough oil getting through to lubricate all of the parts properly.

When you have low oil volume or low oil pressure, you’ll commonly hear a “clattering noise” coming from the engine’s valves. This can come not only from not enough oil, but from the oil getting too old and starting to break down or foam. Either way, there’s not enough lubrication getting to those parts, so you will have a noisy engine. Simple solution? Change the oil or add additional oil to restore the oil volume to its proper level. Also keep in mind that if the oil level is too low, it becomes that way because oil was consumed over time by a mechanical issue, like an oil leak. Adding more oil will make the noise go away, but it won’t solve the underlying cause of the noisy engine – the oil leak.

Tapping Hydraulic Lifters

Sometimes, you get engine noises caused by faulty hydraulic lifters. These make a tapping sound that can occur when the vehicle is cold or hot, depending on the exact cause of the problem with the lifter. By this, we mean that a hydraulic lifter can go bad because of wear, dirt, or even a sticking check valve.

When you have a bad lifter, it will be signified by a ticking sound. This ticking happens at a fast pace; it may even sound almost like a tapping sound. Whatever is the ultimate cause for the lifter going bad will have caused it to lose internal oil pressure. Since the lifter is self-adjusting, this causes a ticking sound.

Can motor oil or an oil additive fix this kind of problem? Sometimes. It depends. If the lifter is malfunctioning because the oil hasn’t been changed in a while, a simple oil change may be enough to correct the issue and quiet the engine. When the oil isn’t changed often enough, it will become dirty and cause the internals of the lifter to become dirty as well, leading to the oil pressure loss we mentioned earlier.

This can also happen if the incorrect weight of oil is used. While you have a certain amount of latitude in the weight of oil you select (lighter weight oils can give you better gas mileage), if the oil is too light or too heavy, it can bleed out of the lifter when the engine is off. Either that or it won’t be pumped fast enough into the lifter when the engine is turned on, leading to this noisy engine problem.

You may be interested in these other posts on Car Care:

• 5 Things We Do to Destroy Our Engines and How to Remedy Our Errors
• Getting Good Gas Mileage - The 3 Engine Components You Need to Check
• Should You Clean Your Car's Engine?