How Often Should You Change Synthetic Oil? A Guide to Intervals

Oil is one of the most important fluids our vehicles use, for obvious reasons.

Changing it whenever the time comes to do so is also one of the easiest and most common preventative maintenance measures that you can take to ensure that your vehicle lasts as long as possible.

Not all oil is created equally, and because of technological improvements over the past twenty years, synthetic oils have risen to the top of the motor oil pyramid.

This has changed the way we think about motor oil, has the ability to help our vehicles last longer, and has increased the amount of time our vehicles can go between oil changes.

Man pouring synthetic oil into a funnel that passes it through his car's engine

It might be more expensive to buy, but the experts are beginning to recommend full synthetic oils for everyone, regardless of the age, make, or model of your vehicle.

Let’s take a look at what synthetic oil is, why they are better than conventional oils, and how they can increase the oil change intervals in your vehicle.

What Is Synthetic Oil?

The definition of synthetic is “something resulting from synthesis rather than occurring naturally,” or to put it more simply, something that is artificial or manmade.

In the case of motor oil, this is only somewhat true.

Synthetic motor oil is still made from a base crude oil. It is just refined or synthesized to varying degrees, and is classified into five different groups according to the American Petroleum Institute.

At the very least, Group III can start to be classified as synthetic oil, while Group V is considered full-synthetic oil.

These oils are highly manufactured to produce uniform molecule size, and are made with multiple additives to provide the desired characteristics of a certain manufacturer’s motor oil.

In other words, synthetic oil is artificially engineered from a refined base mineral oil to produce certain characteristics that wouldn’t naturally be present in its base form.

Why Should You Use Synthetic Oil?

If you don’t change your own oil, chances are that whoever does that for you may already be using at least a synthetic oil blend oil in your vehicle, if not a fully synthetic motor oil.

This is becoming more popular as time passes, considering the advantages it provides.

A study conducted by AAA found that 47% of vehicle engines actually performed better in multiple categories with synthetic oil rather than with conventional oil.

Some vehicles such as high performance vehicles, luxury vehicles, and many German brands actually require the use of synthetic oil to run properly.

If you aren’t using this type in your vehicle yet, there are many good reasons you should.

It Can Prevent Sludge Buildup

Because synthetic oil is manufactured, its molecular makeup is uniform in size, unlike conventional motor oils which vary in size.

This means that less friction is produced, and less sludge buildup will occur within your engine.

It Can Clean Your Engine

It also has many oil additives, some of which specifically help clean your engine from previous oil deposits.

Older engines can greatly benefit from this.

It Is More Resistant to Thinning and Thickening

It can be specifically manufactured to resist becoming too thick or too thin when certain temperatures are achieved.

They can also offer a wider range of all-season temperature flexibility for year-round usage.

It Can Prolong the Life of Your Engine

All of these benefits can add up to a longer lifespan for your engine.

If it runs cleaner, cooler, and better with synthetic oil, you will get more out of it.

It Can Last Longer Between Change Intervals

One of the most important aspects of using this type is that it is engineered to be more resistant against molecular breakdown.

All oils are susceptible to breaking down after time and use, but synthetic oil is made to be more resistant to all the normal factors that would normally cause oil to break down, including heat, use, and time.

How Often Should You Change Synthetic Oil? How Long Does Synthetic Oil Last?

Synthetic oil has changed the way we have always perceived oil, including how long your vehicle can go before the oil needs to be changed.

Better engineering methods have pushed the boundaries of what used to be normal, even though boundaries do still exist.

The “3000 Mile Myth” Is Just a Myth

You have probably heard that you need to change your motor oil every 3000 miles. More recently, 5000 miles has started to become the new “3000 miles.”

That is generally something of the past.

This used to be true with older vehicles which required conventional oils, but synthetic oils are so much better today and are so resistant to breakdown, that changing your oil every 3000 (or even 5000) miles is becoming a waste of time and money.

7500 Miles Is Becoming “the Norm”

7500 miles, or one to two times a year, is becoming the new “normal”, especially for newer vehicles.

Most manufacturers and mechanics that use synthetic oils are saying that 7500 miles between an oil change interval is completely normal for just about every vehicle in which they are used.

10,000 Miles Is Possible for Some Oils

Depending on which type is being used, you may be able to go 10,000 miles (or about one year) before changing your synthetic oil.

Not every synthetic oil brand recommends this when using their product, but not every oil is made the same way, either.

A high-grade synthetic oil will most likely be able to go for longer distances before changes due to the advanced chemical makeup and additives with which it is manufactured.

10000-15000 Miles Is Achievable with Extended Performance Oil

Several General Motors, Ford, and Toyota vehicles use formulas that are meant to last for at least 10,000 miles.

Jaguar uses a special formula that is able to last for up to 15,000 miles, which is the current limit for any vehicle on the market.

Extended performance synthetic oils are available on the market and usually recommend a 10,000 mile change interval, and sometimes even more. These are usually the most expensive motor oils available.

Many New Vehicles Have a Change Oil Indicator Light

Many modern vehicles can tell you when you need to change their synthetic oil.

Usually, a light will come on in the gauge cluster letting you know that an oil change is needed.

Consumer reports found that some vehicles they tested could have been safely driven several thousand more miles before a synthetic oil change was actually necessary after the change oil light came on.

A light like this eliminates the need to constantly track the exact number of miles you’ve driven; therefore, the change interval for synthetic oil may vary from time to time in a vehicle with a change oil light.

Don’t Forget to Change the Fuel Filter

The fuel filter is another important part of an oil change.

The general rule remains that the fuel filter should be changed at the same time as the oil gets changed. However, due to better engineered synthetic oils, every other oil change is becoming more widely accepted.

If you suspect your fuel isn’t performing optimally, familiarise yourself with bad fuel filter symptoms to make a more educated guess.

What Factors Affect How Often You Should Change Synthetic Oil?

So, how do you know when it’s time to change your car’s synthetic oil?

There are several factors to consider when trying to figure out how often you should do such a change in your vehicle, especially if you’ve never had synthetic oil put into your vehicle before.

How Old Is Your Vehicle?

Age doesn’t always affect how long you can drive in between changes.

The lower side of change intervals is often recommended for older vehicles at between 5000 and 7500 miles, especially if there are leaks, and because older engines can burn more oil due to wear and tear.

How Do You Use Your Vehicle?

Even when synthetic oil is used, how you drive your vehicle affects how quickly oil breaks down.

Stop-and-go traffic is hard on your engine and its oil. This line of thinking is becoming harder to justify, with better oils becoming more ubiquitous in the market, but it still has traction and some relevance.

Driving your vehicle in harsher conditions will generally require more frequent changes. For many mechanics, the recommended oil change intervals is once every 5000 miles for harsh driving conditions with synthetic oil.

Is Your Vehicle Turbocharged?

Turbocharged vehicles have skyrocketed in popularity due to the need for smaller, more fuel efficient engines.

Turbocharged engines generally require more oil to stay cool and functioning properly, so shorter intervals are often recommended, even when synthetic oil is used.

What Type Are You Going to Be Using?

There is no hard and fast rule that says synthetic oil has to be made with a certain type of additive or compound. So, every manufacturer has their own formulas for their own products.

This could cause two full synthetic oils from two manufacturers to have completely different recommended change intervals.

So, always read the label or check the manufacturer’s website to see exactly what is recommended for a specific synthetic oil you purchase.

What Will Happen If You Don’t Change Your Synthetic Oil or Wait Too Long to Do So?

Even though synthetic oil is known to be superior in almost every way to conventional oil, it is still car oil, and will eventually break down with use and time.

So, this means that you still have to change the synthetic motor oil in your vehicle. Not doing so could result in severe engine damage or engine failure.

As oil breaks down, it becomes dirty and thin and will not provide appropriate lubrication for all engine components. This will cause overheating due to increased friction of moving parts.

Premature wear of engine components, seal and gasket failure, and eventual engine seizing could occur in the worst case scenarios.

Are There Any Other Tips or Tricks I Need To Know About?

Just because there is a maximum mileage limit on change intervals doesn’t mean you can push the boundaries.

Most upper limits set by synthetic oil producers is still within operational range by design, but just because it lasts longer than regular oil doesn’t mean it is invincible.

Always check your owner’s manual for appropriate oil change intervals.

Just because 7500 miles between oil changes is common for synthetic oil life doesn’t mean it is the best for your particular vehicle. Don’t also assume that 10,000 miles is achievable out of every one of these formulas that you purchase.

Read the product description for manufacturer specific stipulations and limits first, to stay on the safe side.

Every vehicle is designed in a specific way, and the manufacturer always knows best. So, it’s always best to change the oil according to their timeframe.

Also keep in mind that not driving your vehicle around as much doesn’t mean the synthetic oil doesn’t need to be changed.

As good as synthetic oil is, not driving your vehicle won’t make it last longer. Even synthetic oil breaks down as it ages.

Watch this video for some more important tips on synthetic oil change intervals.

Conclusion

Synthetic oil is undoubtedly the king of modern motor vehicle oils today. Technology has improved its capability to lubricate, protect, and even revitalize our vehicle engines.

They are not immune to wear and tear, though. They will break down and wear out just like any other oil – they just do it more slowly than others.

As they continue to improve and reach throughout the entire automotive market, be aware of what they can offer so you don’t change your oil too many times.

Also be aware of their limitations, so you don’t forget to change your synthetic motor oil on time, or be tricked into thinking it will last forever (which it won’t).

Always read your owner’s manual to get the best synthetic oil for your vehicle, and to make sure your oil change intervals are being followed to prolong the life of your ride!

Shawn Furman

I've had a passion for cars since 8 years old, and been a subscriber to Auto Week magazine since my 10th birthday.Ever since I turned old enough to drive, I have driven as many vehicles as possible, while teaching myself how to perform maintenance and upgrade work on every vehicle I've owned.For the past 10 years, I've been honing my skills as a vehicle hobbyist, in recent years also enjoying writing car reviews, opinion articles, vehicle how-tos, car-buying guides, and even provide individual consultations for those who need car-buying advice.In addition to writing for Vehicle Scene, I currently write for Autolist, and also own and operate my own vehicle blog website, The Unlimited Driver.

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