Before you add the oil clean off the fan and oil hole using an all purpose cleaner.
Bearing used in ceiling fan.
But it is necessary if your fan has sealed bearings.
The oil to use in lubricating a ceiling fan s bearings is very specific.
Using the wrong type can clog up the bearings and ruin the fan oftentimes requiring a full replacement.
Faulty bearing causes noise in ceiling fan.
To oil a ceiling fan use a non detergent electric motor oil which is safe to use with an electric motor.
Turn off the power to the room your fan.
My ceiling fan would sometimes not start and making rumbling sounds bearings i did not want to replace or tear down so lifted plastic cover on top and liberally sprayed machine oil over exposed bearing through slots underneath wd 40 this has cured problem perfectly just dry bearings would probably be better to use spray grease if you have cheaper than new fan or bearings and only a few.
Then slowly pour 1 2 ounces of oil into the oil hole.
This video will show you how to change ceiling fan bearings.