Checking the engine oil is the simplest health check you can do, yet most drivers get the timing wrong or misread the dipstick. Done properly, it warns you about wear and leaks long before a warning light does.
Do it on a level, warm-off engine
Park on flat ground and turn the engine off. If it was just running, wait five to ten minutes so the oil drains back into the pan. Checking too soon gives a low reading.
Read the dipstick
Pull the dipstick, wipe it clean, push it fully back in, then pull it again. The film of oil should sit between the two marks. Near the low mark means top up soon. Above the high mark can mean overfilling, which is also bad.
Check the colour and feel
Fresh oil is amber and smooth. Very dark, gritty oil means it is overdue for a change. A milky, cream colour can mean coolant is mixing with the oil, which needs a mechanic.
Frequently asked questions
How often should I check the oil?
Once a month and before any long trip is a good habit, more often if the car burns or leaks oil.
Can I add any oil to top up?
Use the grade in your owner manual. Mixing a very different grade is not ideal, but topping up with the correct one is fine.
To choose the right oil, see our engine oil guides.
