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). An oil with this trademark symbol conforms
to the current engine and emission system protection standards and fuel
economy requirements of the International Lubricant Standardization and
Approval Committee (ILSAC), comprised of U.S. and Japanese
automobile manufacturers.
To protect your engine’s warranty use Motorcraft SAE 5W-20 or an
equivalent SAE 5W-20 oil meeting Ford specification WSS-M2C930-A.
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 unnecessary and could lead to engine damage that
is not covered by Ford warranty.
Change your engine oil and filter according to the appropriate schedule
listed inscheduled maintenance information.
Ford production and aftermarket (Motorcraft) oil filters are designed for
added engine protection and long life. If a replacement oil filter is used
that does not meet Ford material and design specifications, start-up
engine noises or knock may be experienced.
It is recommended you use the appropriate Motorcraft oil filter or
another with equivalent performance for your engine application.
2008 Navigator(nav)
Owners Guide (post-2002-fmt)
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Maintenance and Specifications
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At the next opportunity, safely pull off of the road, remove the fuel filler
cap, align the cap properly and reinstall it. The check fuel cap
lamp
or “check fuel cap” message may not reset immediately; it may
take several driving cycles for the check fuel cap lamp
or “check fuel
cap” message to turn off. A driving cycle consists of an engine start-up
(after four or more hours with the engine off) followed by city and
highway driving.
Continuing to drive with the check fuel cap lamp
or “check fuel cap”
message on may cause the
lamp to turn on as well.
If you must replace the fuel filler cap, replace it with a fuel filler
cap that is designed for your vehicle. The customer warranty may
be void for any damage to the fuel tank or fuel system if the
correct genuine Ford or Motorcraft fuel filler cap is not used.
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 vacuum in
the fuel tank may damage the fuel system or cause the fuel cap
to disengage in a collision, which may result in personal injury.
Choosing the right fuel
Use only UNLEADED fuel or UNLEADED fuel blended with a maximum
of 10% ethanol. Your vehicle was not designed to run on E85 fuels that
are blended with a maximum of 85% ethanol. 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. Studies indicate that
these additives can cause your vehicle’s emission control system to
deteriorate more rapidly.
Repairs to correct the effects of using a fuel for which your vehicle was
not designed may not be covered by your warranty.
2008 Navigator(nav)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
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