Ask three people how often to change your oil and you will get three different answers, usually based on whatever was true decades ago.
This guide gives the real answer for modern cars, including how oil type, driving conditions and Brisbane’s heat change how often your car oil should be changed, so you protect the engine without wasting money on services you do not need.
Here is what we will cover:
- The modern oil-change interval
- Synthetic versus conventional oil
- What shortens the interval (heat, short trips, towing)
- Why the logbook interval matters for warranty
- What happens if you leave it too long
How often should you change your car’s oil?
Most modern cars should have their oil changed every 10,000 to 15,000 kilometres or every 12 months, whichever comes first, while many older engines and those running conventional oil are closer to 5,000 to 7,500 kilometres.
The old rule of changing every 5,000 kilometres no matter what is out of date for most cars on the road today. Better oils and tighter-built engines have stretched the interval, and the right number for your car is the one in its handbook, not a figure from a workshop wall chart.
For a closer look at the real-world numbers, our guide on how often you really need an oil change goes a little deeper on the modern intervals.
When you are due, our team can take care of it, and you can book a car service in Brisbane that keeps the oil and everything around it in good shape.
| Engine / oil type | Typical interval | Notes |
|---|---|---|
| Modern, full synthetic | 10,000 to 15,000 km / 12 mo | Follow the logbook |
| Older / conventional oil | 5,000 to 7,500 km | Shorter by design |
| European / performance | Per manufacturer (often 15,000 km) | Specific oil grade required |
| Hard use (heat, towing, short trips) | Shorten the interval | Brisbane heat counts |
Why has the interval got longer?
Modern full synthetic oils hold up to heat and stress far better than the oils of twenty years ago, and engines are built to finer tolerances. Together that is why a current car can safely run much longer between changes than your first car ever could.
Whichever comes first, why time matters too
Oil degrades with time as well as distance. A low-kilometre car that sits for months still needs its oil changed on schedule, because the oil collects moisture and loses its protective qualities even when the engine is barely used.
Synthetic or conventional, does it change the interval?
Yes, full synthetic oil generally allows a longer interval than conventional oil because it resists heat and breakdown better, which is why modern cars specifying synthetic can safely run 10,000 kilometres or more between changes.
The key is to use what the manufacturer specifies. Synthetic is not automatically better for every engine; it is better for the engines designed around it. Putting the right oil in is what lets you use the longer interval safely.
There is a fair bit of marketing noise around engine oil, and our piece on the truth about engine oil cuts through the upsell so you know what your car genuinely needs.
Can I switch to synthetic?
Usually yes, if the engine suits it, but confirm the correct grade first. The grade and specification matter more than the brand, and the handbook or a quick check with your mechanic settles it.
Does the filter change every time?
Yes. The oil filter is replaced with every oil change. Fitting fresh oil through an old, clogged filter undoes much of the benefit, so the two always go together.
What shortens the oil-change interval?
Frequent short trips, towing, heavy loads and sustained heat all shorten the safe oil-change interval, because they stop the oil reaching full operating temperature or accelerate its breakdown, which is common in Brisbane conditions.
This is where the handbook figure is a starting point, not the final word. The handbook assumes fairly gentle, mixed driving. Brisbane summers, stop-start suburban runs and a loaded car or trailer all push the oil harder, and that means changing it sooner.
If you have noticed drops on the driveway as well, our guide on what causes an oil leak explains why the level falls and what to do about it.
For a tailored interval based on how and where you actually drive, our Brisbane mechanics can set one that fits your car.
Why are short trips hard on oil?
On a short trip the oil never fully warms up, so moisture and unburnt fuel that would normally boil off stay in the oil. Over time that thins and contaminates it, which is why a car used only for short hops needs more frequent changes than the kilometres alone suggest.
Does towing or heat matter?
Both raise the oil’s working temperature and shorten its life. Towing loads the engine, and sustained heat is hard on any oil, so a car that tows or lives in the Brisbane sun benefits from a shorter interval.
What happens if you leave the oil too long?
If you leave engine oil too long it thickens, sludges and loses its ability to protect, which accelerates engine wear, can trigger warning lights, and on a new car can put your logbook warranty at risk.
Old oil is not just tired oil; it turns into a sludge that starves parts of lubrication and traps heat. The damage builds quietly until something lets go, and by then the repair costs many times what the oil change would have. People still ask how often is an oil change truly necessary, and the honest answer is: often enough that the oil never reaches that state.
Can old oil damage the engine?
Yes. Sludge and breakdown over time accelerate wear on bearings and other internals, and that wear is permanent. A few skipped oil changes can shorten an engine’s life considerably.
Does a late oil change void warranty?
On a new car, missing the logbook intervals can jeopardise a warranty claim, because the manufacturer expects the schedule to be kept. Our logbook servicing to manufacturer spec keeps everything stamped and on time so the warranty stays intact.
Conclusion
The right oil-change interval is the one in your logbook, adjusted for how and where you drive. Get it right and it is some of the cheapest insurance an engine can have, protecting it for years for the price of a service.
If you want the correct oil, the correct interval and no upsell, the team at Car One Automotive can keep your engine looked after.
Frequently Asked Questions
How Often Should I Change My Car’s Oil?
Most modern cars run every 10,000 to 15,000 km or 12 months, whichever comes first, on full synthetic oil. Older engines or those on conventional oil are often closer to 5,000 to 7,500 km. Always follow your logbook, and shorten the interval if you do mostly short trips.
Does Synthetic Oil Last Longer?
Yes. Full synthetic resists heat and chemical breakdown far better than conventional oil, which is why modern engines that specify it can run longer between changes. It also flows better on cold starts and protects tighter modern engines, so using the grade your handbook lists really matters.
Do Short Trips Affect Oil Change Frequency?
Yes. Frequent short trips stop the oil from fully warming up, which lets moisture and fuel build up and dilute it instead of burning off. This ages the oil faster than the distance suggests, so the interval should be shortened for mostly-short-trip, stop-start driving.
What Happens if I Change My Oil Late?
Old oil thickens, oxidises and forms sludge, which reduces its ability to protect and accelerates engine wear on bearings and moving parts. On a newer car, missing the logbook intervals can also put your warranty at risk, so staying on schedule protects both the engine and your cover.
Should the Oil Filter Be Changed Every Time?
Yes. The oil filter is replaced with every oil change, because a used filter is already holding trapped contaminants that would immediately dirty the fresh oil. Reusing it also risks a partially blocked filter restricting flow, so a new filter each time is standard practice for good reason.
