New oil is always the best for your bearings, correct?

Most new oil in a drum may not be as clean as you think, and you need to know why and what you can do about it.

I always assumed that new oil was clean oil–until I started working with a customer who was having premature bearing failures. Upon testing a fresh sample of the brand of oil they were using, we found that in most cases it did not meet the equipment manufacturer tolerances.

How Can New Oil be Dirty?

How can oil in a sealed container be anything but clean? Even the best manufacturing processes are going to produce or encounter contamination. Crude oil comes out of the ground extremely dirty, but during processing it is filter cleaned. However, just the presence of dust or moisture in the air when the product is being processed or transferred can lead to cleanliness issues.

Part of new oil contamination also depends on how the oil arrives at your facility. For example, you may receive drums and pails that are either filled at the blend plant and delivered by your preferred distributor or filled at the distributor from oil in tankage. You may receive bulk shipments either from the distributor or directly from the oil blending plant. In all these cases, contamination can be introduced during the process of filling storage containers or tanks.

And then there is the question of the condition of drums: are they new or reconditioned? Could they already have contamination within? There can also be cross-contamination of bulk loads and mislabeled containers, as well.

In addition, how you store the oil can impact its cleanliness. When oil is stored where the outside of the containers can get dusty or dirty, then you risk introducing that contamination when you use that drum, bottle, or pail. And if you change out or top off the oil when the machine is dusty or in a dirty environment, it can contaminate the new oil.

And oil might look clean to the unaided eye, but particles can do damage even when they aren’t large enough to see. Just because it takes a microscope to see it does not mean it can’t damage your motor bearings.

Why Dirty Oil is a Big Deal

Experts agree that issues with lubrication are a major cause of mechanical system failure, and that includes the bearings on your electric motor. That is why oil cleanliness is so important for your motor’s reliability and performance.

Remember that oil serves three key purposes: reducing friction, protecting components from surface-to-surface contact, and conducting heat away. When it fails in any of these goals, it compromises the performance and reliability of your motors. And particulate contamination in the oil for your bearings can damage surfaces, increase friction, and make it more difficult to conduct heat away. And brand new, dirty, oil can seriously damage your bearings.

Also keep in mind that newer equipment often has much tighter and more stringent tolerances when it comes to lubrication. That means that the cleanliness levels of the oil must be higher than you would expect with older machinery. What might have worked perfectly well for a 20-year-old motor may not work with the new motor your facility invested in last year.

The Effects of Dirty Oil

Particulate matter in the oil is going to start causing tiny pieces of metal to flake off. These flakes of metal add to the contamination already present, resulting in a cycle of premature wear and damage that’s going to eventually affect the performance of your motor. And given long enough, the bearings will be totaled, and your electric motor comes to a (literal) grinding halt. Then you have the downtime and costs associated with pulling the motor and installing new bearings (along with any other components that may have been damaged as a result).

And if you do not make sure the oil you use on the new bearings is clean, then the cycle will simply start over again.

The Benefits of Clean Oil

When you make sure the oil you use is clean, the result is more uptime, zero failures due to dirty lubrication, and enhanced motor reliability. And the costs involved with testing, filtration, and oil fill carts are minimal compared to downtime, repairs, and new bearings. In fact, experts believe that cleaning your oil as little as one cleanliness code can increase your equipment life by 35%


If your bearings are failing prematurely, it might be time to take a good look at the cleanliness levels of your so-called, new oil. This can be accomplished with some basic tests that will show you if that is where your problem lies. In addition, new oil should be filtered for all applications in which reliability is a priority. And that is why you should only work with a repair facility that ensures that the new oil they plan to use in your machines really is clean oil.