It is best to follow the Severe Service maintenance schedules found in most new car owner’s manuals, with a few exceptions:
Air filters need to be inspected regularly and replaced as
often as needed, regardless of mileage or time. Dirty air filters can
increase fuel consumption and exhaust emissions.
Fuel filters should be replaced yearly and/or at every
tune-up, especially on fuel injected cars. The fuel filter in a vehicle with
electronic fuel injection passes a much larger volume of fuel than its
counterpart in a carbureted application. If the tank is dirty or rusty,
constant fuel recirculation can pick up a lot of debris that ends up in the
filter. If the filter plugs, the engine is starved for fuel or unfiltered
fuel is allowed to bypass the filter. The latter can damage injectors.
Oil filters need to be replaced at every oil change (every
six months or 3,000 miles in most cases) despite the advice in many owner’s
manuals to only change the filter at every other oil change. A new filter is
cheap insurance against major engine damage, so why take unnecessary risks?
Few owner’s manuals have a suggested change interval for the
automatic transmission fluid (ATF) or fluid filter unless the vehicle is
used for towing. Most transmission specialists say the best preventative
maintenance for prolonging automatic transmission life is to change fluid
and filter every two years or 30,000 miles.
Follow the manufacturer’s recommendations on the specific
type of ATF to use. The type of ATF should match the specs required for the
All GMs, most late model
Chryslers and many imports use Dexron II. All 1988 and later Fords require
Mercon ATF. Most universal ATF fluids are acceptable for either of these.
Older Fords or imports require Type F fluid.