“While synthetic generally holds up better and can serve for more miles, it is equally important to not extend oil changes beyond the time interval recommended by the manufacturer—typically six months or a year if it is a motor that is not driven many miles or on many short trips.”
In fact, if you wait too long for an oil change, your smooth and clean oil will turn into dirty sludge. When this happens, your engine must work harder to fight through the buildup of muck. It loses its lubrication, and decreases heat absorption. This means that your car will be susceptible to major issues.
Most conventional oil brands will have a shelf life of about 5 years. Synthetic oil and synthetic blend oil will last about 7-8 years, and maybe even longer. If you cannot find the expiry date, make sure you use up any half-opened or unopened motor oil bottles within 2-5 years of the manufacturing date.
It used to be normal to change the oil every 3,000 miles, but with modern lubricants most engines today have recommended oil change intervals of 5,000 to 7,500 miles. Moreover, if your car's engine requires full-synthetic motor oil, it might go as far as 15,000 miles between services!
MATH. A modern car rated for 7500 miles per oil change or 1 year should be perfectly fine for 4000 miles or two years...
It is recommended to get your oil changed at least twice a year, even if you haven't driven those thousands of miles that are normally recommended. Oil, like anything, degrades over time, and if you have oil degrading in your engine for months and months and months, that's not good for your vehicle.
For those who drive only 6,000 miles or less per year, Calkins said manufacturers typically recommend changing the oil once a year. Moisture and other contaminants can build up in the oil, especially with frequent cold starts and short trips, so owners shouldn't let it go more than a year.
If you happen to miss an oil change and the motor oil starts to lose effectiveness, these parts won't be properly lubricated. This could result in pieces grinding together or simply not moving at the rate your car needs to perform. Additionally, motor oil works to regulate engine temperature.
The Old Standard for Oil Changes Has Been Updated
But times have changed, and so have the oil change standards. Now the general recommendation is about every 5,000 miles or 6 months. And it could be up to about every 7,500 miles or every 12 months if your car is new and you don't drive it very hard.
On average, vehicles are estimated to need an oil change every 3,000 miles or every six months. This can vary based on your driving habits, your driving frequency, the age of your vehicle, and the quality of the oil you use. If you drive a newer vehicle, you might be able to safely wait a little longer between changes.
Motor oil can only last for a certain period of time. That's why it comes with an expiry date. For this reason, oil goes bad with time just by sitting in the engine. Over time, it becomes less viscous thus less efficient in maintaining proper lubrication between moving components.
Simply put, the shelf life of conventional motor or "lube" oil is up to five years. It's not something that goes bad in a couple of months. It's impossible to predict exactly how long motor oil shelf life is because petroleum stability (how well it resists change in its properties) is situation-dependent.
Over time, petroleum-based oils will degrade or break down from the heat and pressure inside the engine. As this occurs, the chemical composition of the oil changes and it becomes contaminated. After thousands of miles, petroleum-based oils are unable to protect the engine and must be replaced.
Fresh oil has a transparent light brown colour but over time this will start to turn darker and can eventually become thick and black. Once your oil loses its transparency and turns black it's a good sign that it's time to change your oil as it may contain particulates that can cause gunk to form in the engine.
Oil Change Interval for Low-Mileage Vehicles
Ideally, an oil change is recommended after your vehicle is driven for 3000-5000 miles. In case the vehicle has not reached the mileage threshold, then you may begin to wonder whether you still need to get the oil changed. The answer to this pressing question is yes.
The quick-lube chains usually recommend it be done every three months or 3,000 miles, but many mechanics would tell you that such frequent changes are overkill. Indeed, most car owner's manuals recommend changing out the oil less frequently, usually after 5,000 or 7,500 miles.
Unlike synthetic blends or conventional oils, fully synthetic oils won't break down and will protect your engine for longer—sometimes as much as 250,000 miles.
Synthetic blends hold up longer and won't break down, even after 5000 miles of driving. Newer cars also have better filtration systems, allowing you to safely drive 5000 miles between oil changes.
If you're changing your oil more frequently than necessary, it won't help your car. It doesn't harm it either, but you're wasting money, time and resources. Keep in mind, too, that throwing away oil that's still usable puts a strain on the environment.
Every time the engine is started, the oil is contaminated with blow-by soot, raw gasoline and condensed moisture. Unless the engine gets regular extended highway travel, these contaminants remain in the oil.” If you drive in one or more of these conditions in a typical week, you may need to change your oil more often.
Myth: Once you switch to synthetic oil, you can never switch back. This is one of the most persistent myths about synthetic oil—and completely untrue. You can switch back and forth at any time. In fact, synthetic blends are simply a mixture of synthetic and conventional oils.
Synthetic oil is resistant to breaking down under high temperatures, so it will last longer in your engine. This means you can go longer between oil changes without damaging your engine if you use synthetic oil.
A few disadvantages of synthetic oil to be aware of include: Probably the most glaring downside of synthetic oil is the cost. The price of synthetic oil is around two to four times the price of conventional oil. Synthetics may be more prone to additives precipitation during cold storage conditions.
Overall, full synthetic oils provide better engine performance and protection than conventional and synthetic blend motor oils.