Motor oil is meant to help cool and lubricate the engine’s components while removing contaminants, which are collected in the oil filter. If your vehicle is overdue for an oil change, it may have built up contaminants like soot, dust, metal particles, dirt, or water, and may no longer properly cool and clean the inside of the engine. This can lead to increased friction, drag, and wear, and can seriously damage engine components, including the bearings, piston rings, and more. Contaminated oil may be caused by a larger problem such as an internal engine leak or a failed oil filter as well, so it is important to inspect your oil levels and condition regularly.
It’s easy to ignore a necessary oil change, especially if your oil pressure or other warning systems don’t alert you to low oil levels. Whether you don’t see a dashboard warning or reminder light, aren’t familiar with your vehicle’s oil change interval, or don’t know the signs of low motor oil, remaining vigilant in keeping the oil in your vehicle fresh may not always be at the top of your list.
Not only does oil clean and cool the internal components of your engine, but the correct oil levels can improve fuel economy and engine performance by reducing friction and wear. Having too little oil, on the other hand, can lead to decreased engine performance and fuel economy. If ignored for too long, low oil levels can cause the engine to seize or the bearings or piston rings to wear excessively and fail, meaning you would need to rebuild or replace the engine to return your vehicle to service. Avoiding or forgetting an oil change for too long could seriously damage the engine in your car, truck, or SUV, so let’s discuss what can happen over time if you do not change your motor oil regularly.
Oil Becomes Contaminated or Saturated
Low Oil Levels Can Cause Motor Oil to Burn
If motor oil is not replaced when the level is low, the remaining oil can burn due to high engine temperatures. Any less than a quart of oil circulating throughout your engine can cause serious issues, and the oil remaining in the engine can suffer from evaporation that can cause it to wear out, burn, or thicken too much to work properly.
Low Oil Levels Can Cause Engine Noise
Without oil, your vehicle’s engine cannot be properly lubricated, causing metal components to make direct contact without oil between them acting as a cushion. When engine components experience metal-on-metal contact, they can make a slight tapping or knocking sound, or you may hear camshaft bearing noise due to low oil pressure. Lifters can begin to tick, which is often one of the first signs of low oil pressure or oil levels. Similar noises from the engine can also be caused by oil that is too old and has a reduced viscosity that no longer allows it to provide protection against friction.
Oil Can Become Sludge
If your motor oil hasn’t already evaporated from the engine due to heat, the oil can thicken into sludge as it ages and when oil levels are too low. New motor oil is able to properly suspend the contaminants and debris collected, but when oil is old and at reduced levels, the debris in the oil can congeal onto your internal engine components. The formation of sludge can be accelerated by variables like moisture, oxygen, and debris that has made its way into the oil. Not only will sludge become tar-like, but it can clog your engine’s oil passages and it will no longer be able to absorb heat from the engine, which can lead to a blown head gasket or your engine seizing. Engine flush products can help remove the presence of sludge, but in some instances, certain engine components will be damaged beyond repair if oil changes are neglected long enough to create engine sludge.
Do It Right with Regular Oil Changes
As simple as an oil change is, keeping old oil running through your vehicle could cost you more than time. An easy way to prevent missing or forgetting an oil change is to get in the habit of checking your oil. Some check oil levels once a month, while other drivers choose to inspect their oil every time they are filling their gas tank or at other regular events that can be used as a marker.
You may want to consider looking in your owner’s manual to see if your vehicle is equipped with a Low Oil Pressure warning light, and ensure that the light or the oil pressure gauge is working properly to prevent engine failure from low oil levels or oil circulation problems. Changing your habits to keep consistent with regular oil changes, as well as using our helpful video that can lead you through your next oil change step-by-step, can help you keep your vehicle on the road for as long as possible.
If you're not comfortable performing your own oil changes, we would be happy to refer you to a local shop or service center to help you complete your maintenance.
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