Adding engine oil
1. Check the engine oil. For instructions, refer to
Checking the engine oilin this chapter.
2. If the engine oil level is not within the normal
range, add only certified engine oil of the
recommended viscosity. Remove the engine oil filler
cap and use a funnel to pour the engine oil into the
opening.
3. Recheck the engine oil level. Make sure the oil
level is not above the MAX mark on the engine oil
level indicator (dipstick).
4. Install the indicator and ensure it is fully seated.
5. Fully install the engine oil filler cap by turning the
filler cap clockwise 1/4 of a turn until three clicks
are heard or until the cap is fully seated.
To avoid possible oil loss, DO NOT operate the
vehicle with the engine oil level indicator
and/or the engine oil filler cap removed.
Engine oil and filter recommendations
Look for this
certification trademark.
Use SAE 5W-20 engine oil.
Only use oils“Certified For Gasoline Engines”by the
American Petroleum Institute (API). To protect your
engine’s warranty use Motorcraft SAE 5W-20 or an
equivalent 5W-20 oil meeting Ford specification
WSS-M2C153–H.SAE 5W-20 oil provides
optimum fuel economy and durability
performance meeting all requirements for your
vehicle’s engine.
Do not use supplemental engine oil additives,
cleaners or other engine treatments. They are
2004 Mustang(mus)
Owners Guide (post-2002-fmt)
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Maintenance and Specifications
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The fuel system may be under pressure. If
the fuel filler cap is venting vapor or if you
hear a hissing sound, wait until it stops before
completely removing the fuel filler cap. Otherwise,
fuel may spray out and injure you or others.
If you do not use the proper fuel filler cap,
excessive pressure or vacuum in the fuel
tank may damage the fuel system or cause the fuel
cap to disengage in a collision, which may result in
possible personal injury.
Choosing the right fuel
Use only UNLEADED FUEL. The use of leaded fuel
is prohibited by law and could damage your vehicle.
Do not use fuel containing methanol. It can damage
critical fuel system components.
Your vehicle was not designed to use fuel or fuel
additives with metallic compounds, including
manganese-based additives.
Repairs to correct the effects of using a fuel for
which your vehicle was not designed may not be
covered by your warranty.
Octane recommendations
Your vehicle is
designed to use
“Regular”unleaded
gasoline with pump
(R+M)/2 octane rating of 87. We do not recommend
the use of gasolines labeled as“Regular”that are
sold with octane ratings of 86 or lower in high
altitude areas.
Do not be concerned if your engine sometimes
knocks lightly. However, if it knocks heavily under
most driving conditions while you are using fuel with
the recommended octane rating, see your dealer or
a qualified service technician to prevent any engine
damage.
87(R+M)/2 METHOD
2004 Mustang(mus)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
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