I take the drives apart as far as I can go, then wipe off any old grease. It's just not a good idea to be spraying ANYTHING around a floppy drive. After that, I wash all the parts in very hot water.. just rinse them.. no soap.. taking care not to get water into motors / steppers.

Let dry 24 hours.

Then I reassemble using a synthetic phono lube.. VERY sparingly.. on any parts that were originally lubed. WD-40 is NOT a long term lube.. and is way too lightweight to serve anything more than a "loosening bolts" or cleaning purpose.

Synthetic is necessary so the lube doesn't dry up down the road.

These methods have resulted in many perfectly working floppy drives.

~ J