If you’ve got a car and either a garage or shed, the chances are you’ve got some old engine oil kicking about. Likely it’s nothing more than a 1-liter top-up bottle, given to you at your last car service, or maybe the one before, or the one before that. Maybe it’s a 4-liter can you bought to do that between oil changes you never got around to doing. It leaves you wondering then… Does motor oil expire?
You’re not sure how long it has been there so the question is… Does motor oil expire or can I still use it? Follow this article to find answers to your questions.
Shelf Life For Motor Oil
There is a general consensus of terminology coming from the oil companies that unused, unopened, and stored in its original container out of extremes of temperature, motor oil will last for an “extended period”. They then go on to suggest that the oil shouldn’t be used after a few years; the exact period varying between 2 years (according to Total) up to 5 years (Mobil).
So whilst motor oil manufacturers say we should responsibly dispose of oil after a few years they all stop short of saying that the oil does actually expire. Clearly, there is a vested interest in their future sales here so to get to the truth about oil we need to drill down deeper.
But it’s not without merit… The primary purpose of motor oil is for lubrication. Inside the internal combustion engine, hard metal surfaces slide backward and forwards across each other at high speed and at very high temperatures.
The oil forms a fluid barrier between the moving parts. Hence, lowering friction and, crucially, reducing wear on major engine components. The latter includes pistons, connecting rods, crankshaft, and of course the cylinder linings of the block itself.
Secondly, the oil also acts as a coolant, drawing heat away from the engine as it circulates, and third, it keeps the engine clean by carrying away dirt and debris from high-wear areas.
Motor Oil Expiration Date
The manufacturers’ advice on storage gives some clues as to what might happen to degrade the oil. Extremes of temperature can affect oil in different ways. Too hot and thermal breakdown occurs reducing the oil’s viscosity (its “weight” or thickness). If used, this leads to a decreased flow rate and in turn to increased oil consumption.
In addition, there’s the build-up of deposits and potential damage to engine surfaces. Too cold and sludge will form in the oil, blocking engine oil passages and eventually becoming too thick to flow at all.
Another possible degradation cause is oxidation, more likely with a container that’s been opened, which is where the oil molecules react with oxygen molecules in the air. This time, viscosity increases forming sludge and sediment. Oxidizing oil can also increase acidity and start to rust or corrode any metal surfaces it contacts.
An opened, part-used container also renders the oil more susceptible to contamination from water condensation or dirt, both of which reduce its effectiveness as a lubricant.
Synthetic vs Conventional Oil
Simply put, yes, the type of oil matters a lot. The key to this is whether the oil is synthetic and what additive ingredients there are. Both conventional and synthetic oil began life coming out of the ground.
But, synthetic oil is further refined, distilled, purified, and broken down to a basic molecular level. From this point, the oil’s molecular structure can be rebuilt and customized to suit a specific purpose, such as the greater demands of heat tolerance in modern engines.
Even though this more uniformly engineered base oil is already an improvement over conventional oils, it is further improved through a blend of additive compounds. These extra ingredients counter the typical breakdown caused by maintaining viscosity at extremes of temperature.
It’s otherwise accomplished with detergents and dispersants which delay sludge build-up. Furthermore, isolating contaminants by suspending them in the oil and counteracting the effects of oxidation.
How Does Engine Oil Work
Everything that could happen to break down oil in a container, is even more likely in use inside an engine. It is subjected to much higher temperatures and, of course, mechanical action.
As conventional oils in use start to break down straight away, the maximum recommended driving between oil changes used to be only a few thousand miles. Depending on whether you drive hard miles – characterized by lots of short trips where the engine oil barely warms up – or easy miles – such as longer highway journeys – your engine oil can last a full-service interval such as 18,000 miles.
The biggest issue in use now is contamination. As the oil circulates around the engine it picks up dirt such as soot and microscopic slivers of metal worn away from the moving parts. This is good in that it takes the dirt away from the engine but even with a good oil filter it can eventually become saturated with debris and start to form a sludge.
How To Store Motor Oil
Only put into your engine the type and grade of motor oil recommended by the car’s manufacturer. The brand is less of an issue but it’s probably best not to mix brands as they’ll have different additive recipes which may not work as effectively together.
Make sure the oil and oil filter is changed according to the mileage intervals given in the owner’s manual or if the car has been sat unused for more than a few months. Whilst premium brand fully synthetic motor oils can be quite expensive and you might be reluctant to waste them, the cost is trivial compared to having major surgery on your engine to replace worn components caused by filling up or topping off with degraded oil.
So does motor oil expire? Yes, it can but depending on the conditions and the type of oil it might take a long time. Unless there is an expiry date on the container and it’s still in the future or you know exactly how long you’ve had it and how it’s been stored, it’s time to take those cans, part-cans, and bottles of motor oil down to your local recycling center and remove the temptation to use it.
How To Properly Dispose Of Motor Oil
Motor oil disposal is often ignored by car manufacturers yet is a task many of us will have to carry out.
Most companies will advise that you change your car’s oil every 5,000 or so miles, to ensure that the engine runs smoothly and that your car will continue to perform optimally. However, few manufacturers will actually tell you what to do with the dirty oil once it has been changed. And more to the point, how to dispose of it.
The type of oil you will most likely dispose of is waste oil such as fuels and lubricants, which are commonly used in the average car engine.
Does Motor Oil Expire, Disposal Tips #1: How Dangerous Is It
The irritating news is that you can’t just put oil in the trash or pour it down the drain. That’s because oil is classified as a highly toxic, hazardous chemical. Clean oil is relatively safe. But once it is used in an engine and is no longer clean, it becomes a carcinogen. The oil company Pennzoil said this regarding oil’s toxicity;
‘Used oils may contain harmful impurities that have accumulated during use. The concentration of such impurities will depend on use and they may present risks to health and the environment on disposal. All used oil should be handled with caution and skin contact avoided as far as possible. Remarks: Continuous contact with used engine oils has caused skin cancer in animal tests.’
Bearing this in mind it is important to use good practice when you store, handle, or dispose of the oil. This also explains why dumping oil in a landfill is illegal in many parts of the world and can lead to a hefty fine – in short, the initial time and effort saved by dumping it is not worth it.
Does Motor Oil Expire, Disposal Tips #2: Easiest Way To Collect It
When changing your motor oil it is advised that a trash bag is put underneath the pan. That way, the majority of the oil can be collected in an easily transportable way with minimal effort.
If any oil is spilled it can be straightforward to clean up if you know what you’re doing. Pouring cat litter or sawdust over the split will help to absorb the puddle before it stains anything,
After letting it soak up for a couple of hours, sweep the pile up and secure it in a bin bag – be sure to wear gloves and wash your hands thoroughly after finishing.
To ensure that the ground underneath remains free from stains a squirt of dishwashing soap and a brief scrub with a hard bristle brush will do the trick.
Unpainted concrete may be trickier to clean effectively. So instead, mix a 50:50 solution of laundry detergent and bleach. Then, pour it on, and wipe up the residue with paper towels. After that, once again use gloves and wash your hands after.
Does Motor Oil Expire, Disposal Tips #3: Storing It For Transport
One simple way to efficiently collect and safely store the oil is to use a plastic bottle. Such as the one it came in, or an old water bottle. A storage unit that can be sealed airtight is recommended.
The easiest way to get the oil from the bin bag as mentioned earlier is to place a funnel in the neck of the bottle. Then, hold the bin bag over it, and puncture a hole in the bottom. This will minimize spillage while allowing you to collect the oil easily. You may want to put down some paper towels to soak up any rogue drops.
Does Motor Oil Expire, Disposal Tips #4: Where To Take It
For motor oil disposal this can be taken to a recycling plant if it’s clean. However, if it is dirty as is more likely the case, and contaminated with other substances it must be taken to a local waste disposal center.
Many auto shops and garages also accept oil that they will safely dispose of. So, check on Google for those in your area.
This process differs depending on whether you are disposing of household oil waste or if you are a business. As a business there are strict legal requirements you must meet if you produce, store, collect, transport, recycle, or dispose of oil as waste.
You should not dispose of waste oil from a business at the same place you would leave household oil waste. Google how this differs for your area as the law changes.
Upon transporting oil from your household to a disposal site this location will then be legally responsible for disposing of it and your work is done!
Does Motor Oil Expire: Some Interesting Facts…
How Long Can Motor Oil Be Stored
Unused, unopened, and stored in its original container out of extremes of temperature, motor oil will last for an “extended period”. They then go on to suggest that the oil shouldn’t be used after a few years; the exact period varying between 2 years (according to Total) up to 5 years (Mobil).
Does Oil Go Bad Over Time
Extremes of temperature can affect oil in different ways. Too hot and thermal breakdown occurs reducing the oil’s viscosity (its “weight” or thickness). If used, this leads to a decreased flow rate. In turn, it leads to increased oil consumption, the build-up of deposits, and potential damage to engine surfaces. Too cold and sludge will form in the oil, blocking engine oil passages and eventually becoming too thick to flow at all.
How Long Is Oil Good For
Depending on the conditions and the type of oil it might take a long time. Unless there is an expiry date on the container and it’s still in the future or you know exactly how long you’ve had it and how it’s been stored.
Can You Use Expired Motor Oil
No. Oil shouldn’t be used after a few years; the exact period varies between 2 years (according to Total) and up to 5 years (Mobil).
Does Synthetic Oil Go Bad
Simply put, yes, the type of oil matters a lot. The key to this is whether the oil is synthetic and what additive ingredients there are. Both conventional and synthetic oil began life coming out of the ground. But, synthetic oil is further refined, distilled, purified, and broken down to a basic molecular level.
How Many Months Does Synthetic Oil Last
According to Total, the exact period varies between 24 months and up to 60 months (Mobil).
How Long Can You Keep Unused Motor Oil
Clearly, you can keep it as long as you like. But, the best performance of the oil would be lost after the first 5 years.
Does Motor Oil Have An Expiration Date
There is no official expiration date on oil like we get on food. However motor oil is the same as tires, they will last for a long time but they go past their best after 5 years.
Does Motor Oil Go Bad Sitting In An Engine
In the engine, the oil will start to degrade over time yes. There are lots of opportunities for the oil to oxidize and experience thermal breakdown from use.
Is It OK To Use Expired Oil
Old oil may not be as efficient as brand-new motor oil. The cost of oil is relatively cheap compared to engine components. So, you might be best purchasing new oil for your car’s engine and protecting it against failure
Does Motor Oil Degrade If Not Used
Yes over time the oil will go past its best. It will last decently long unopened compared to open. However, engine oil manufacturers state that oil will be at its best for 5 years.
Does Synthetic Oil Last Longer Than Regular Oil
Chances are yes, synthetic oil is further refined, distilled, and purified specifically for use in car engines.
How Long Can Motor Oil Be Stored
Unused, unopened, and stored in its original container out of extremes of temperature, motor oil will last for an “extended period”. They then go on to suggest that the oil shouldn’t be used after a few years; the exact period varying between 2 years (according to Total) up to 5 years (Mobil).
Frequently Asked Questions
If you still have some unanswered questions, our FAQs here might help shed some light…
What Oil Does My Car Take
In the US, the most common type of oils that many cars use is following either the SAE 5W-30 or SAE 10W-30 standard. It’s crucially important to top up your engine with the right type of oil, designed specifically for your car. In particular, note the viscosity of the oil. Otherwise, using the wrong oil could cause serious issues with your engine. This is since it won’t be able to lubricate or cool it down as effectively. If you’re unsure about what type of oil your car uses, all you need to do is refer to the owner’s manual. There should be at least one mention of the recommended oil type. Some cars also have stickers on the oil reservoir cap or within the engine bay to remind you.
Does Oil Go Bad
In short, the answer to does motor oil expire is a solid yes. Engine oil, regardless of whether they’re conventional, semi-synthetic, or fully synthetic in nature, they will go expire and go bad eventually. Over time, motor oil will lose its effectiveness for lubricating engines and keeping them cool. Specifically, the chemical compound would start to break apart, making them less efficient in operation. It can sometimes be okay to leave it be for several years. However, this is dependent on how you’re storing the oil – temperature, exposure to dirt, or whether the bottle’s been opened. Therefore, be wary of the expiry date, and don’t open the bottle unless you need to.
Motor Oil Brands To Avoid
For the most part, you should be able to easily find a reliable and trusted bottle of motor oil practically anywhere. However, there are certain brands that make poor-quality oils, which may have adverse effects on your engine. At the very least, their performance isn’t worth the expense over big-brand motor oils. Some of the worst engine oil brands include Liberty Motor Oil, Petrola Motor Oil, Xpress Lube Pro, Questron, and Quaker State Q. If you see any of these brands on the shelves of your local auto parts store, run away. No matter how cheap they are, it’s far better to get a bottle from a well-known company, instead.
Does Synthetic Motor Oil Expire
When asking about does motor oil expire, we do wonder about synthetic oils. Many oil companies advertise them as “long-lasting”. In practice, the advanced and synthesized chemistry with synthetic oils does result in actually long-lasting fluids that don’t need changing as often. In some cases, certain synthetic motor oils could last idling inside an engine for 5 years or so before going bad and expiring. Meanwhile, its lifespan lasts for quite a while between oil changes compared to conventional engine oil, too. On average, synthetic oil requires a change every 7,500 to 15,000 miles.
Does Motor Oil Expire After Opening
Does motor oil expire, you might ask? Yes, but how long it takes depends greatly on how you store said oil. In particular, whether or not you’ve opened the bottle. If the bottle is left unopened and the oil is sealed inside, it could last between 2 to 5 years. Granted, it would continue to lose some of its effectiveness over time. But what if the bottle is only half-opened? In this case, the oil would start to lose its effectiveness much more rapidly. It’s recommended that you shouldn’t keep it for any longer than 1 year after the bottle’s been opened, and the seal broken. Be wary of any dirt, oxidation, and other contaminants that could pollute the oil.
Approved Tools
These tools have been tried and tested by our team, they are ideal for fixing your car at home.
-
AI Car Expert: I am here to help you with your car questions. Ask me anything.
My car burns so much oil, that after 3K miles it practically changes the oil itself.
Haha. That is not ideal.
FanGuider, actually the dirt and contaminants will stay in and accumulate in the engine so you need to change it regardless.
Only after 1year.
No don’t need off. Top-up the engine oil.
I have a case of AMSOIL 20W-50 synthetic. It’s rolling on probably 5 years old or so. It’s been stored in house. I just changed the oil in my 08’ Ultra Classic a couple months ago. This oil wasn’t cheap and I would hate to have to toss it. It’s in plastic containers. Just looking for some opinions. Thanks
I use Mobil synthetic in my 95 Honda Civic change it every 5 k and car had over 200k when sold. I due trans and radiator every 30 k.
If oil is in the ground for thousands of years I believe it can last in a bottle for a long time. Many years unopened.
Yes but in the ground the oil is not exposed to extreme heat or moisture.
Oil endures constant heating and cooling in your motor, from below freezing to 225 degrees F in a normal motor. So keeping it in your house at near-constant cool temps is NOT going to degrade it significantly. USE IT!
Engine oils are expensive but dirt and heat made it polluted so you need to change it on regular basis. You can store oil for a longer time but engine oil does have an expiry date, and it becomes less effective. If the motor oil is not used for an extended period you need to change it for better performance.
My car burns so much oil, that after 3K miles it practically changes the oil itself.
ou can store oil for a longer time but engine oil does have an expiry date, and it becomes less effective.
Engine oils are expensive but dirt and heat made it polluted so you need to change it on regular basis. ???
Thanks for the comment, Simon!
Yep, that’s about right. As time passes, the engine oil will start to break down its chemical compounds. The heat from the engine, especially, will break it down so that it’s no longer as effective at lubrication (i.e. reduced friction between your engine’s many moving parts) or thermal transfer to help cool your engine down.
Oil would also wear out due to the amount of contaminants and impurities inside the engine, such as metal shavings and whatnot. These would also cause the oil to turn into a thick, viscous sludge. Contaminated oils have a limited ability to lubricate and cool your engine, not to mention cause problems with oil pressure.
For that reason, oil changes are one of the most consequential car-related services and maintenance jobs that you absolutely have to pay close attention to.
Even under ideal storage conditions after 3 years the oil is no longer viable.
And if it’s been stored in a shed, it could be bad after only a year
Thanks for the comment, Jim Navotney!
Agreed! The earlier you use it the better 🙂
When should I change my engine oil?
Change your engine oil in 10000km (6000 miles) or ones in year. Don’t over think 🤔 and don’t forget it.
Thanks for the comment, David!
It should be noted that oil change intervals vary wildly from one car to another, and it also depends on numerous other factors such as the type of oil used. In some cases, you might have to change the oil every 3,000 miles, while some cars can go as far as 6,000 miles before an oil change is needed. Overall, it’s best that you refer to your owner’s manual to get a more specific guidance on when might be right to change the oil.
Thanks for explaining how thermal breakdown can make motor oil unusable eventually. I’d like to get a used oil pickup service soon because my home is a bit far from the busier parts of the city. It’s difficult to get car services so I tend to just change my oil in my own garage.
Thanks for the comment, Alice Carroll!
A used oil pickup service is certainly a fantastic idea! For the environment’s sake, not to mention the well-being of those around you, proper disposal of motor oil is crucial. Alas, there are some who don’t pay close attention to it. For you, there are loads of mobile services that pick up and properly and safely dispose or recycle old motor oil, such as Safety-Kleen, Crystal Clean, Sun Coast Resources, Aaron Oil, Noble Oil, and plenty more.
Do Synthetic Oils Have a Longer Shelf Life?
Thanks for the comment, Alex Coleman!
Typically speaking, synthetic motor oil does have a longer shelf life in storage, yes. Although, it does depend on what kind of additives are in it. For example, there have been proven claims that synthetic engine oil can last up to 5 years in storage if contained properly.
What are the signs of expired engine oil?