How to Check Engine Oil
Checking oil takes one minute and prevents most engine failures. Do it monthly and before long trips. Low or dirty oil is the leading cause of preventable engine wear.
Reading the Dipstick
- Park on level ground and let the engine cool for a few minutes
- Pull the dipstick, wipe it clean, reinsert fully, then pull again
- Oil should sit between the two marks — add if below the low line
Choosing Oil
Your owner's manual lists the correct viscosity (such as 5W-30). Using the wrong grade can hurt fuel economy and protection. Synthetic oils last longer but must still be checked regularly.
Warning Signs
Dark, sludgy oil or a burning smell means it is time for a change. A drop in level between checks can signal a leak or consumption issue worth a mechanic visit.
When to Check
Check oil on a level surface with the engine off and cool, or after a short wait per the manual. Hot, sloped readings are wrong and can lead you to overfill — which is its own problem.
Reading the Dipstick
- Wipe the stick, reinsert fully, pull again
- Oil should sit between the two marks
- Color should be amber, not black and gritty
Topping Up
Add the grade listed in the manual, a little at a time, then recheck. Overfilling can foam the oil and damage seals. If you add a quart every few hundred miles, you have a leak or burn to fix, not just a top-up.
When Oil Looks Wrong
Milky oil suggests coolant leaking into the engine; gritty black oil suggests long neglect. Both warrant a shop visit, not just a top-up. Catching contamination early can save the engine from internal damage.
Synthetic vs. Conventional
Synthetic oil resists heat and lasts longer but costs more. Use what the manual specifies — switching down to save money can shorten intervals and risk protection the engine was designed around.
How Often to Check
Once a month and before long trips is enough for most cars. Newer engines burn little, but a sudden drop between checks signals a leak or consumption worth a shop visit.
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