Step 1 unlock your car.  Step 2 get inside the front passengers seat.
Step 3  Open the Glove Box.  Step 4 remove the owners manual.  Step 5
Open the owners manual to the glossary.  Step 6 Look up "vehicle
maintenance schedules".  Step 7 Look over the maintainance schedule and
consider BOTH mileage and time.  For example it might say.  "Change the
motor oil ever 5,000 miles or every 6 months, whichever comes first."
It might also say, "For vehicles that go through prolonged engine
idling, stop and go traffic, and dusty conditions.  Change the oil evey
3,000 miles or ever 3 months.  Whichever comes first."

But you MUST check the owners manual since every car is different and
every manufacturer is different in their maintainance recomendations.

HINT HINT.  Keep a notebook.  A small one.  Inside your glovebox.
Write down EVERYTHING you do to your car.  For example one log entry
might say.  "8/12/07  6,000 miles.  Changed oil and oil filter.  Used
5W30 pennsoil"  This is your way of remembering when was your last oil
change.  You should also include entries like "5/20/08  30,000 miles.
Changed engine air filter, oil change, radiator fluid flushed."  You
can refer to your repair/work log book every other week as well as the
owners manual as a way to remember what has been done and what needs to
be done in order to keep the car running like a top.

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