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How do you know or does synthetic motor oil ever expire? Unfortunately, there is not a straightforward answer since the longevity of the oil is influence by a variety of factors. Below we discuss some of the factors that must be considered before determining whether synthetic oil can still be used. This is an important consideration given that expired oil might not have the protective factors that can help protect your car.
All drivers have had the experience of needing to change their oil. Some drivers opt for a professional oil change through their local car mechanic while other drivers opt for a do-it-yourself oil change.
Regardless of the method you choose to change your oil, you have likely encountered questions when it comes to changing your oil. One of the most common questions that drivers ask about oil is whether synthetic motor oils can go bad.
Here’s 8 Important Factors of Oil Expiration?
One way to avoid the problem of oil expiration is to only purchase the amount of oil that you will need in order to change your oil for this one time. However, given the cost savings of buying oil in bulk, some drivers prefer to stock up on the oil. In general, you should expect that your oil will last at least five years.
This five-year suggestion is based on the assumption that you store the oil according to the storage instructions that come printed on your motor oil can.
If your motor oil comes with an expiration date printed on the container, which is less than five years, you should abide by the printed date. After the date on the container has passed, make sure that you properly dispose of the oil. After the expiration dates have passed, there is no longer a guarantee that the synthetic additives will still function properly.
When thinking about shelf life, it is important to understand that the composition of motor oil does not last forever. Things such as the specific additives will determine how long the motor oil will last. While these are two of the most important factors in determining the life of the synthetic motor oil, there are some other factors involved.
One of the factors that you have the most control over is the temperature at which the motor oil is stored. Storing the oil somewhere between 40 – 85 degrees Fahrenheit is the best option. You should also make sure that you find a place to keep the oil where the temperatures will not be variable. This is because very low and very high temperatures can impact the oil’s ability to lubricate the engine.
As you might expect, bottles of oil that have not been opened tend to last longer than bottles of oil that have already been opened. Thus, you should try to open only one bottle of oil at a time and use any opened bottles for your next oil change. This will prevent you from having multiple bottles of opened motor oil.
When storing your oil, there are a couple of other important factors to consider. One is that you will want to store the oil in an area that is not prone to humidity. If humidity seeps into your oil, you might experience alterations in your oil that could lead to added microbes or sludge.
Both of these pose problems for your engine. Lastly, you will want to keep the oil away from dust. Any dust that makes its way into your oil is certain to aid in clogging your engine more quickly.
#1 How Will I Know if My Motor Oil Is Expired?
While it can be hard to tell for certain if your oil is expired, there are some steps you can take to determine this. First, look for an expiration date. If the date has passed, throw the oil away. Alternatively, if you have had the oil for more than five years, it is time to dispose of the oil.
If you are unsure, check for the color of the oil. If the oil looks clear, it is likely good to use. However, if you see haziness in the oil it could be an indication that water has gotten into the bottle. Another good indicator of whether the oil is suitable to use is the consistency. If you notice any separation in the motor oil, that is not a good sign and you should throw away the oil. Similarly, oil that is solid, think, or very sticky is also not good to use.
#2 What Is The Shelf Life For Synthetic Motor Oil?
There is no definite time for how long synthetic lubricants should last before expiring. For some manufacturers of synthetic oil such as Mobil, their synthetic oil should last for five years.
Other manufacturers claim that their product can last for an unlimited period. However, it should be stored under specific conditions.
The shelf life of synthetic motor oil depends on a variety of factors. For your synthetic oil to last for a prolonged period, you should follow the manufacturers’ instructions.
You should also make sure to check the expiry date on the container. When the expiry date is crossed, avoid using the synthetic oil in your car engine. The oil may damage your engine components. An expired oil will also not protect your engine and enable it to perform.
Synthetic lubricants are artificially formulated. As such, they come with various additives that help to meet the needs of your engine.
The various additives can affect the shelf life of your synthetic oil. The multiple chemicals used in formulating synthetic oil have different shelf lives.
For instance, if the oil contains elements such as iron and copper, it may have a short shelf life. Copper and iron may catalyze the oxidation of the oil affecting its durability.
Other factors that affect the shelf life of synthetic oil include the storage. You should follow the manufacturer’s instructions on storage. Storage of between 45-85 degrees should be sufficient.
Also, you should store it in a dusty free environment which is free from humidity. An unopened bottle also helps to keep the oil stable for long.
#3 Does synthetic motor oil degrade over time?
Synthetic oil may break down over time because of various reasons. These include the oil getting used and the additives that make up the lubricants.
As you use the vehicle, there are traces of hydrocarbons and water that contaminate the oil.
Most instructions from the manufacturer will tell you to change the oil at least once per year. The duration may, however, be affected by various factors.
For instance, do you use your car for short periods and distances?
Short distance driving and local driving does not allow time for the engine and oil to heat up. You switch on the car, and before the engine can heat up to evaporate the water, you switch off. The water vapor will start diluting the synthetic oil with time.
The diluted oil mixture can lead to the formation of acids and sludge. Eventually, the sludge and corrosion will damage the engine and affect its performance.
Additionally, the additives in synthetic oil may also affect how the oil degrades. When you start using the oil in the engine, the chemical additives will start degrading slowly. This will affect the quality of the oil and its ability to perform.
A change of oil at the scheduled time is necessary. This is irrespective of whether you think the oil has not degraded. Not changing the oil at the scheduled time can void your warranty. It may also affect the lifespan of your engine.
#4 How long does engine oil last once opened?
Probably you are wondering, “Should I use the leftovers for my previous oil changes?” Well, as long as they are stored correctly, nothing should stop you from using them.
Sometimes, you may find that you have accumulated so many leftovers from your previous oil changes. The leftovers may be enough to use instead of buying another container of oil. However, before you choose to use the leftovers, there are a few factors to consider.
First, check the expiry dates of the leftovers. This is important as mixing the leftovers without checking if they are expired may contaminate each other.
Additionally, before using an opened oil, you should ensure that they are well stored. The leftovers may vary in shelf life depending on the storage.
For instance, if you stored your leftover in a humid environment, it may have been contaminated by moisture. It, therefore, will not offer you the necessary protection.
Open leftovers stored in extreme temperatures, dusty environments, and so on may also degrade.
However, if you store the oil for years, then it may not be safe for use. The different additives may start settling out of the oil.
#5 Can motor oil go bad in the bottle?
The general consensus is that synthetic motor oil should last for an extended period. The extended period may vary depending on some factors.
Different brands have different timing for an extended period. For example, Total says that motor oils should last for an extended period of 2 years. But, Mobil puts the extended period at 5 years.
However, there is a consensus that for the motor oil to last, it should be stored in the original container and a conducive environment.
It is best to store the oil away from direct sunlight.
But why should you put the oil away from direct sunlight?
The oil molecules may start reacting with the UV rays from the sun. The sunlight may also cause oxidation of oil which may cause the formation of acids. The acids cause corrosion of the engine parts which reduces its lifespan.
#6 Does unopened motor oil go bad?
If the expiry date of the motor oil has passed, then it is not proper to use it. Even if the bottle is not opened, a crossed expiry date means the oil should be disposed of.
For an expired synthetic oil, the components have disintegrated. You may even have deposits at the bottom of the container. The deposits cannot be re-dissolved into the oil by shaking. The only remedy is to dispose of the lubricant.
Additionally, whether open or unopen, synthetic oil will go bad because of the environment you store it in. Oil should be stored in a cool and dry place. It should also be away from sunlight.
If it is in direct sunlight, the molecules of the synthetic oil will react with the UV rays. This may lead to oxidation of synthetic oil. Oxidation may lead to the formation of acids which may be corrosive to your engine parts.
Also, if you put it in a humid environment, the moisture may get into the acid and contaminate it. High temperatures may also cause the oil to degenerate with time.
Whether the bottle is open or not, you should not use the oil in your car if it has gone bad. If you use it, it will not protect your engine, and it may cause damage to some parts.
#7 Signs of stable or unstable motor oil
To tell if motor oil is stable or not, you should first check the expiry date. If it has crossed the expiry date, then the oil is not stable for use.
Secondly, you should check for the consistency of the motor oil. Typically, motor oils should be clear. If the color starts to change to milk or there is haziness, do not use it. The change in color is an indication that the oil is not stable.
If the oil becomes thick and sticky, then it should not be used. You may also start noticing some particles in the oil. The particles can also form at the bottom of the container. The particles will not re-dissolve even after shaking. You may also notice that the additives in synthetic oil have separated.
#8 Does motor oil go bad inside the engine?
The same thing that happens to oil while in a container happens inside the engine. For instance, high temperatures cause motor oil to disintegrate.
In the engine, there is a generation of a lot of heat. If you use conventional oils, they break down in the high temperatures. T
his leaves your engine prone to friction and wear. Alternatively, you can use synthetic oil that comes with thermal properties. Thus, it withstands the high temperatures to protect your engine even when it heats up.
There is also oxidation happening inside the engine. Oxidation in the engine may cause the formation of deposits. The deposits may affect the performance of your engine by making it unhealthy.
Oxidation may also cause the formation of acids in the engine. This may cause corrosion of the metal parts and other parts of the engine. You should, therefore, look for motor oil with anti-corrosion properties.
Does unused synthetic engine oil ever expire?
Unused engine oil will expire whether it is opened or unopened. Many brands say that their oil lasts for an extended period. After the extended period, the oil should not be used.
The extended period varies for various brands with Mobil giving up to 5 years while Total gives 2 years. After the oil expires, its components disintegrate. You start noticing a change in color, texture, and so on. You may also see deposits forming at the bottom of the container.
For the oil to last for a long time, you should store it properly. Store it in a cool and dry place. As such, the UV lights from direct sunlight will not react with the oil molecules. Also, moisture will not contaminate the oil.
How long can synthetic oil sit in the engine?
How long the lubricant sits in the engine depends on a variety of factors. Many car manufacturers suggest that you should change the oil after about 7,500 miles.
However, the draining interval can extend or reduce. Some of the factors that affect the drain intervals include your driving patterns. For long-distance drivers, the oil drain interval may be shorter than short-distance drivers.
It also depends on the engine type. Old engines are more prone to wear and tear. They produce deposits and contaminants that require you to change the oil frequently.
Most new vehicles have systems that monitor oil quality. The tracking systems check the engine temperatures, the distance of travel, driving conditions, and so on. They then indicate when it is time to change the oil.
Following the manufacturer’s instructions on oil change interval is the best option.
How long does unused oil last?
How long unused oil will last depends on the storage. When properly stored, some synthetic oils can last up to 5 years. You should store your oil in a cool and dry place. This will prevent moisture from getting into the oil and contaminating it.
Direct sunlight makes the oil molecules to react with the UV rays. This causes the oil to deteriorate with time.
Why do you need motor oil for your car?
Inside the engine, there is a lot of movement that is happening. Many surfaces are rubbing against each other as they move. The moving surfaces may cause a lot of friction that will lead to wear and tear. This reduces the lifespan of your engine.
So, the primary purpose of using engine oil is lubrication. The oil forms a thin layer of lubrication around the moving parts. This reduces friction between the moving parts minimizing wear and tear. Thus, you enjoy a longer lifespan for your engine. The movement in the engine also generates a lot of heat. The motor oil works to cool it.
The motor oil also works to clean the engine. As the oil flows in the engine, it collects all the deposits and eliminates them. The oil also prevents the formation of sludge. As such, you have a clean and healthy engine that offers optimal performance.
Is synthetic oil better than conventional oil?
Conventional oil is formulated from crude oil. It does not come with any additives. When the engine heats up, the conventional oils do not withstand the heat. As such, it may not offer the necessary protection to your engine.
For synthetic oils, they are human-made with additives that meet the specific needs of your engine. For instance, it comes with cleaning properties that help to keep your engine clean and healthy. They also come with properties that enable it to withstand the high temperatures.
Do motor oils expire?
Motor oils come with an extended period. The extended period may differ depending on the different brands. For instance, Total gives an extended period of about 2 years, while Mobil gives an extended period of 5 years.
When the extended period is over, the oil is not fit for use. Motor oil goes bad depending on how you store it. That is why you should just buy what you need. However, buying in bulk can be cost-effective. As such, if you buy in bulk, you should make sure you store the oil properly.
The best environment to store the oil will be in a dry place and away from direct sunlight. If you keep in a humid area, the moisture can contaminate the oil. If you store it in direct sunlight, it may cause oxidation of the oil.
Can you use your previous leftovers?
If the leftovers you have are enough to refill your engine, nothing should stop them from using them. However, you should check their expiry date, especially for the oldest leftover to ensure they have not gone bad.
Also, you should ensure that the leftovers have been stored well. Whether they are opened or unopened, the leftovers should be kept away from moisture and air. Through this, they will still be suitable for use when you need them.
How do you know that your oil has gone bad?
The first indicator of oil that has gone bad is the expiry date. Even if the oil is unopened and has been stored well, it should not be used if it is expired.
Secondly, the color can also tell if the oil has gone bad. If the color changes from clear to milk, it is an indication that the oil is bad.
You should also check for the formation of deposits. The deposits can also be at the bottom of the container. If there are deposits, do not use the oil.
Disintegration and separation of the additives also show that the oil is not fit for use. You can even notice some haziness or the oil may become thick and sticky.
Do additives in synthetic oil affect its shelf life?
Yes, they do. Additives are chemicals that come with different disintegration periods. As such, as they degenerate, the motor oil also deteriorates.
Plus, some additives such as copper are catalysts. So, when you use them in oil, they catalyze the oxidation process.
Below is a Handy Video on How To Check date Codes
To make sure that when you purchase a bottle off the shelf, here is a guide on how to read date codes to see if your bottle is in date or how long it is out of date.