It all depends on if your car tends to go 9,000+ miles before letting you know its time to change which is not good on your engine. I suggest you pick a good number like 3k or 5k miles & change it at that same interval everytime
newer cars will, older cars wont.. give it about 5000 mi. between changes.
This must be on the Mazda 3 you mentioned in another question. We don't know the year but if you have a display with the features shown in the source it will remind you.
Depends on the car. Mine has an indicator that comes on. Read your owners manual to find out if yours is so equipped.
I change mine every 3,000 It tells me PERFORM SERVICE.
Will car tell me when its time for oil change
