60-second summary
Here are the key things to know about changing the oil in your car…
Cars typically need an oil change every 6000-12,000 miles, or every 6 or 12 months. Recommended mileages and periods vary between car makers and oil types.
Oil keeps your car running smoothly by reducing friction, reducing wear on moving parts, and preventing the buildup of sludge.
Signs you need an oil change include dark or gritty oil, increased engine noise, warning lights and exhaust smoke.
Milky-looking oil, signs of leaks and sludge buildup indicate potential trouble and should be checked by a mechanic.
Why do cars need oil?
Oil helps keep your engine running smoothly. Without it, things grind to a noisy, damaging stop. Oil helps reduce friction, keep temperatures in check and prevent metal parts from wearing out. It also contains chemicals that maintain viscosity, fight corrosion and clean your engine.
But not all oils are the same. Check your manual to make sure you’re using the right one for your car.
It’s easy to check your oil or to top it up. Changing it over is a messier job that may be best left to a mechanic and is typically done as part of a service.
How often to change your oil
Many cars are recommended to have an oil change every 12,000 miles or every 12 months, whichever comes sooner. For some cars, every 6 months or 6000 miles is recommended. It all depends on things like manufacturer advice, driving conditions and types of oil used.
If you’re using long-life oil, you may be able to go longer without an oil change.
As a matter of routine, changing the oil prevents dirt and grit build-up, which can cause engine damage in both petrol and diesel cars. There are times, however, when an oil change becomes urgent and can’t wait for the next service or routine check.
How to tell when your oil needs changing
Knowing when to change your oil is important for maintaining your car’s health. Here are some signs that it might be time for an oil change:
Dark and dirty oil: Fresh oil is typically amber in colour. If you notice that the oil is dark or gritty, it’s time for a change.
Increased engine noise: If your engine is louder than usual, it could be due to old oil that’s lost its effectiveness.
Oil change or check engine light: Many cars have a light that indicates when it’s time for an oil change. Don’t ignore it.
Exhaust smoke: If you see smoke (not just vapour) coming from your exhaust, it could mean your oil is old or there’s an oil leak.
Oil-related problems
There are a few other tell-tale signs of an oil problem that could require expert help:
Milky or foamy look: Does your oil look like a milkshake or mayonnaise? It could be coolant mixing with your oil, typically from a blown head gasket or blown air cooler. Be sure to get this checked by a professional immediately.
Oil on your drive: Patches of oil where your car was parked are never normal. This indicates an oil leak somewhere and should be checked ASAP.
Sludgy texture: If your oil looks like thick tar, it’s likely breaking down from age, missed changes or too much stop-start driving. Regular oil changes can help, but if it’s bad, you might need an engine flush.
How to check your oil
Always keep an eye on your oil level and check it ahead of any long drive.
Most modern cars use sensors to show the oil level in your in-car display, so you’ll always know when your oil needs a top-up (see next section).
For older cars, checking the oil is a more manual process involving a dipstick. Here’s how to do it:
Make sure the car is parked on level ground and the engine is cold.
Get some kitchen roll or an old cloth, then open the bonnet and find the dipstick. It’s normally a metal stick with a small finger-sized yellow ring on the end.
Remove the dipstick and wipe it clean. You’ll see it has ‘MIN’ and ‘MAX’ markers towards the tip of the stick.
Replace the dipstick and leave for a few seconds.
Remove it again and look at where the oil comes up to. If it’s between ‘MIN’ and ‘MAX’, you’re good to go. If it’s close to ‘MIN’ or below, you need to top up with the appropriate oil. If it’s significantly above the ‘MAX’ marker then head to a garage to get the level adjusted.
How to top up engine oil
If your car’s oil level is looking a bit low, you can top it up yourself by pouring more in through the oil filler cap. (In older cars, you’ll usually find this next to the dipstick.) Check you’re using the right oil (see next section), add a little, check the level, and so on.
If you find you’re needing to top up the oil regularly, you may have a leak, in which case it’s a good idea to get your car checked by a mechanic.
You can change the oil over completely yourself, but it’s messy and you’ll need to dispose of the used oil appropriately. Getting this done during your service is likely to be a more convenient option.
Knowing what engine oil to use
If you are keen to keep on top of your oil maintenance, picking the right type of engine oil is key. Here’s how to pick the right one:
Check your manual – it’s the best source for the exact oil type, viscosity and standards your car needs
Look at the oil cap – some cars have the recommended oil or correct viscosity printed right on the cap for easy reference
Visit the manufacturer’s website – if you’ve misplaced the manual, most car brands list oil specs online
Use an online tool – many oil brands let you enter your car’s make, model and year to find the right match
Ask a pro – If you’re unsure, a mechanic or dealership could point you in the right direction.
Electric and Hybrid cars
Do electric cars use oil?
Electric cars (EVs) don’t use engine oil so don’t require traditional oil maintenance.
Do hybrid cars use oil?
Even though they’re partly electric, hybrid cars have an internal combustion engine, so they still need oil changes – just as a purely petrol or diesel car does. This includes plug-in hybrids – even if you run them mostly on electric power.
FAQs
Does an engine oil and filter change count as a service?
A service is a check of your car’s mechanical and electrical parts. An engine oil and filter change might be included, but it’s not the same thing.
When should I check my oil level?
It’s recommended that you check your engine oil level every few weeks, rather than waiting for the oil light to come on the dash.
What is oil viscosity and what impact does this have on my engine?
Viscosity refers to how easily your oil pours. Thicker oils have a higher viscosity than thinner ones, which can make them harder to pour in cold weather.
If an oil is too thick, it may mean the engine has to work harder – making it more difficult to start. Consult your car’s manual to know which oil is right for you.
What does it mean when the oil light turns on?
If your oil warning light comes on, it could mean you’re low on oil or even that your engine is overheating.
While this doesn’t necessarily mean your car is unsafe to drive, you should pull over as soon as possible and check your oil levels. If in doubt, see a mechanic.
How much is an oil change?
How much you pay to have your oil changed will depend on where you live and what type of vehicle you drive. The average cost of a standard oil and filter change is £90.65, according to 2024 RAC figures.
Garages tend to base their prices on your engine size and what type of oil you need. Synthetic or specialist oils often cost more, for example, but won’t need to be changed as often.
Julie is passionate about delivering a great customer experience and rewarding people for saving on their insurance through our loyalty and rewards programme. She’s spoken to the media, including outlets like Sky News, about car and home insurance, as well as our Meerkat rewards scheme.
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