To check your engine oil, park on level ground, switch off, wait a few minutes, then pull the dipstick, wipe it, push it fully back in and pull it out again. The oil should sit between the two marks. Top up only if it is low, a little at a time, and never above the top mark.
How much oil your car takes in total depends on the engine, and the handbook has the figure. Here is the whole process.
Checking the level
- Park on level ground, so the reading is true.
- Switch off and wait about five minutes so the oil can run back to the sump.
- Open the bonnet, find the dipstick (often with a brightly coloured handle) and pull it out.
- Wipe it clean with a cloth, push it all the way back in, then pull it out again.
- Read the level. The oil should be between the minimum and maximum marks.
Many newer cars have no dipstick and show the oil level on the dashboard instead. Check the handbook for how to read it.
What the oil should look like
- Amber to dark brown is normal, and it darkens with use.
- Very black and gritty oil is overdue a change.
- A milky or creamy colour can mean coolant is getting into the oil. Stop driving and get it checked.
- A strong smell of fuel is also worth a check.
Topping up
Use the oil grade your handbook specifies. The grade is printed on the old bottle and in the manual, and the wrong one can cause trouble. Add a small amount at a time, wait, and recheck.
Never fill above the maximum mark. Too much oil can foam, strain the engine and damage the catalytic converter.
How much oil does my car take?
Most cars take somewhere between about four and six litres for a full change, but it varies a lot. The exact figure is in the handbook, and a garage can look it up from your registration. The difference between minimum and maximum on the dipstick is usually around one litre.
If the oil light comes on
A red oil light means low oil pressure. Stop somewhere safe, switch off and check the level. Do not carry on driving. It is covered in our guide to dashboard warning lights.
Quick answers
How often should I check my oil?
Once a month and before a long journey is a good habit. Older cars may need it more often.
Is it bad to overfill the oil?
Yes. Too much oil can foam and strain the engine. If you have overfilled, have some drained.
Can I mix oil brands?
In an emergency, topping up with a compatible oil of the right grade is fine. For a full change, use one oil of the specified grade.
Does a service include an oil change?
Yes. Every service, from an interim to a full, includes an oil and filter change.