
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 and 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.Refer toMaintenance product specifications and
capacitieslater in this chapter for more information.
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 in thescheduled maintenance information.
Ford production and Motorcraft replacement 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.
Maintenance and Specifications
342
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

WARNING:Keep batteries out of reach of children. Batteries
contain sulfuric acid. Avoid contact with skin, eyes or clothing.
Shield your eyes when working near the battery to protect against
possible splashing of acid solution. In case of acid contact with skin or
eyes, flush immediately with water for a minimum of 15 minutes and
get prompt medical attention. If acid is swallowed, call a physician
immediately.
WARNING:Battery posts, terminals and related accessories
contain lead and lead compounds.Wash hands after handling.
Because your vehicle’s engine is electronically controlled by a computer,
some control conditions are maintained by power from the battery. When
the battery is disconnected or a new battery is installed, the engine must
relearn its idle and fuel trim strategy for optimum driveability and
performance. To begin this process:
1. With the vehicle at a complete stop, set the parking brake.
2. Put the gearshift in P (Park), turn off all accessories and start the
engine.
3. Run the engine until it reaches normal operating temperature.
4. Allow the engine to idle for at least one minute.
5. Turn the A/C on and allow the engine to idle for at least one minute.
6. Release the parking brake. With your foot on the brake pedal and with
the A/C on, put the vehicle in D (Drive) and allow the engine to idle for
at least one minute.
7. Drive the vehicle to complete the relearning process.
•The vehicle may need to be driven 10 miles (16 km) or more to
relearn the idle and fuel trim strategy.
•If you do not allow the engine to relearn its idle trim, the idle
quality of your vehicle may be adversely affected until the idle
trim is eventually relearned.
If the battery has been disconnected or a new battery has been installed,
the clock and radio settings must be reset once the battery is
reconnected.
Maintenance and Specifications
344
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

When this occurs the vehicle will still operate. However:
•The engine power will be limited.
•The air conditioning system will be disabled.
Continued operation will increase the engine temperature:
•The engine will completely shut down.
•Steering and braking effort will increase.
Once the engine temperature cools, the engine can be re-started. Take
your vehicle to an authorized dealer as soon as possible to minimize
engine damage.
When fail-safe mode is activated
You have limited engine power when in the fail-safe mode, so drive the
vehicle with caution. The vehicle will not be able to maintain high speed
operation and the engine will run rough. Remember that the engine is
capable of completely shutting down automatically to prevent engine
damage, therefore:
1. Pull off the road as soon as safely possible and turn off the engine.
2. Arrange for the vehicle to be taken to an authorized dealer.
3. If this is not possible, wait a short period for the engine to cool.
4. Check the coolant level and replenish if low.
WARNING:Never remove the coolant reservoir cap while the
engine is running or hot.
5. Restart the engine and take your vehicle to an authorized dealer.
Driving the vehicle without repairing the engine problem
increases the chance of engine damage. Take your vehicle to an
authorized dealer as soon as possible.
FUEL FILTER
Your vehicle is equipped with a lifetime fuel filter that is integrated with
the fuel tank. Regular maintenance or replacement is not needed.
Maintenance and Specifications
350
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

WHAT YOU SHOULD KNOW ABOUT AUTOMOTIVE FUELS
Important safety precautions
WARNING:Do not overfill the fuel tank. The pressure in an
overfilled tank may cause leakage and lead to fuel spray and fire.
WARNING:The fuel system may be under pressure. If you hear
a hissing sound near the fuel filler door (Easy Fuel™ “no cap”
fuel system), do not refuel until the sound stops. Otherwise, fuel may
spray out, which could cause serious personal injury.
WARNING:Automotive fuels can cause serious injury or death
if misused or mishandled.
WARNING:Fuel ethanol and gasoline may contain benzene,
which is a cancer-causing agent.
Observe the following guidelines when handling automotive fuel:
•Extinguish all smoking materials
and any open flames before
fueling your vehicle.
•Always turn off the vehicle before
fueling.
•Automotive fuels can be harmful
or fatal if swallowed. Fuels such as gasoline and ethanol are highly
toxic and if swallowed can cause death or permanent injury. If fuel is
swallowed, call a physician immediately, even if no symptoms are
immediately apparent. The toxic effects of fuel may not be visible for
hours.
•Avoid inhaling fuel vapors. Inhaling too much fuel vapor of any kind
can lead to eye and respiratory tract irritation. In severe cases,
excessive or prolonged breathing of fuel vapor can cause serious
illness and permanent injury.
•Avoid getting fuel liquid in your eyes. If fuel is splashed in the eyes,
remove contact lenses (if worn), flush with water for 15 minutes and
seek medical attention. Failure to seek proper medical attention could
lead to permanent injury.
Maintenance and Specifications
351
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

•Fuels can also be harmful if absorbed through the skin. If fuel is
splashed on the skin and/or clothing, promptly remove contaminated
clothing and wash skin thoroughly with soap and water. Repeated or
prolonged skin contact with fuel liquid or vapor causes skin irritation.
•Be particularly careful if you are taking “Antabuse” or other forms of
disulfiram for the treatment of alcoholism. Breathing gasoline and/or
ethanol vapors, or skin contact could cause an adverse reaction. In
sensitive individuals, serious personal injury or sickness may result. If
fuel is splashed on the skin, promptly wash skin thoroughly with soap
and water. Consult a physician immediately if you experience an
adverse reaction.
•FFV fuel tanks may contain zero to 85 percent ethanol. Any fuel
blends containing gasoline and ethanol should be treated the same as
“Fuel Ethanol.” Flex fuel vehicles have a yellow bezel placed over the
fuel fill inlet.
Pure ethanol is the alcohol which is the intoxicating agent in liquor, beer
and wine. It is distilled from the fermentation of plants such as field corn
and sugar cane. When ethanol is produced for use in motor fuels, a small
amount of gasoline is added to make it unfit for beverage use. The
resulting ethanol blend is called denatured fuel ethanol meaning that it is
denatured with 2% to 5% gasoline and is suitable for automotive use.
During the summer season, fuel ethanol may contain a maximum of 85%
denatured ethanol (Ed85) and 15% unleaded gasoline. The fuel ethanol
has a higher octane rating than unleaded regular or premium gasoline
and this allows the design of engines with greater efficiency and power.
Winter blends may contain up to 75% denatured ethanol (Ed75) and up
to 25% unleaded gasoline to enhance cold engine starts. Severely cold
weather may require additional measures for reliable starting.
Ethanol is more chemically active than gasoline. It corrodes some metals
and causes some plastic and rubber components to swell, break down or
become brittle and crack, especially when mixed with gasoline. Special
materials and procedures have been developed for flexible fuel vehicles
and the dispensers used by ethanol fuel providers.
WARNING:Flexible fuel components and standard unleaded
gasoline fuel components are not interchangeable. If your vehicle
is not serviced in accordance with flexible fuel vehicles procedures,
damage may occur and your warranty may be invalidated.
Maintenance and Specifications
352
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

WARNING:When refueling always shut the engine off and
never allow sparks or open flames near the filler neck. Never
smoke while refueling. Fuel vapor is extremely hazardous under certain
conditions. Care should be taken to avoid inhaling excess fumes.
WARNING:The flow of fuel through a fuel pump nozzle can
produce static electricity, which can cause a fire if fuel is
pumped into an ungrounded fuel container.
Refueling
WARNING:Fuel vapor burns violently and a fuel fire can cause
severe injuries. To help avoid injuries to you and others:
•Read and follow all the instructions on the pump island;
•Turn off your engine when you are refueling;
•Do not smoke if you are near fuel or refueling your vehicle;
•Keep sparks, flames and smoking materials away from fuel;
•Stay outside your vehicle and do not leave the fuel pump unattended
when refueling your vehicle — this is against the law in some places;
•Keep children away from the fuel pump; never let children pump
fuel.
Use the following guidelines to avoid electrostatic charge build-up when
filling an ungrounded fuel container:
•Place approved fuel container on the ground.
•DO NOT fill a fuel container while it is in the vehicle (including the
cargo area).
•Keep the fuel pump nozzle in contact with the fuel container while
filling.
•DO NOT use a device that would hold the fuel pump handle in the fill
position.
Easy Fuel™ “no cap” fuel system
Your fuel tank is equipped with an Easy Fuel™ “no cap” fuel filler
system. This allows you to simply open the fuel filler door and insert the
fuel filler nozzle into the fuel system. The Easy Fuel™ system is
self-sealing and protected against dust, dirt, water and snow/ice.
Maintenance and Specifications
353
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

When fueling your vehicle:
1. Turn the engine off.
2. Open the fuel filler door.
3. Slowly insert the fuel filler nozzle fully into the fuel system. Pump fuel
as normal.
4. After you are done pumping fuel, slowly remove the fuel filler
nozzle—allow about five seconds after pumping fuel before removing the
fuel filler nozzle. This allows residual fuel to drain back into the fuel tank
and not spill onto the vehicle.
Note:A fuel spillage concern may occur if overfilling the fuel tank. Do
not overfill the tank to the point that the fuel is able to bypass the fuel
filler nozzle. The overfilled fuel may run down the drain located within
the fuel filler housing and to the ground.
If the Check Fuel Fill Inlet lamp or Check Fuel Fill Inlet message comes
on, the fuel fill inlet may not have properly closed. The inlet may have
stuck open or debris may be preventing the inlet from fully closing. At
the next opportunity, safely pull off the road, turn off the engine, open
the fuel filler door and remove any visible debris from the fuel fill
opening. Insert either the fuel fill nozzle or the fuel fill funnel (see
Refilling with a portable fuel containerfor funnel location) provided
with the vehicle several times to dislodge any debris and/or allow the
inlet to close properly. If this action corrects the problem, the Check
Fuel Fill Inlet lamp or Check Fuel Fill Inlet message may not reset
immediately. It may take several driving cycles for the Check Fuel Fill
Inlet lamp or Check Fuel Fill Inlet 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/highway driving. Continuing to drive with the Check
Fuel Fill Inlet lamp or Check Fuel Fill Inlet message on may cause the
Service Engine Soon lamp to turn on as well.
WARNING:The fuel system may be under pressure. If you hear
a hissing sound near the fuel filler door (Easy Fuel™ “no cap”
fuel system), do not refuel until the sound stops. Otherwise, fuel may
spray out, which could cause serious personal injury.
Flex Fuel Vehicle (FFV) fuel fill inlet
Flex fuel vehicles have a yellow bezel placed over the fuel fill inlet.
Choosing the right fuel
Use only UNLEADED FUEL and FUEL ETHANOL (Ed75–Ed85).
Maintenance and Specifications
354
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)

The use of leaded fuel is prohibited by law and could damage your
vehicle.
Your vehicle was not designed to use fuel or fuel additives with metallic
compounds, including manganese-based additives.
Note:Use of any fuel other than those recommended may cause
powertrain damage, a loss of vehicle performance, and repairs may not
be covered under warranty.
Octane recommendations
Your vehicle is designed to use “Regular” unleaded gasoline with a pump
(R+M)/2 octane rating of 87. Some stations offer fuels posted as
“Regular” with an octane rating below 87, particularly in high altitude
areas. Fuels with octane levels below 87 are not recommended.
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 authorized dealer to prevent any engine damage.
FFV engines
Your vehicle is designed to use Fuel Ethanol (Ed75–Ed85),“Regular”
unleaded gasoline or any mixture of the two fuels.
Use of other fuels such as Fuel Methanol may cause powertrain
damage, a loss of vehicle performance, and your warranty may be
invalidated.
It is best not to alternate repeatedly between gasoline and E85. If you do
switch fuels, it is recommended that you add as much fuel as
possible—at least half a tank. Do not add less than five gallons (18.9L)
when refueling. You should drive the vehicle immediately after refueling
for at least 5 miles (8 km) to allow the vehicle to adapt to the change in
ethanol concentration.
If you operate your vehicle 50% or more of the time on ethanol, you
should follow a different maintenance schedule. In addition to this, if you
exclusively use E85 fuel, it is also recommended to fill the fuel tank with
regular unleaded gasoline once every 3,000 miles (4,800 km). See
scheduled maintenance informationfor more information.
Fuel quality
Do not add aftermarket fuel additive products to your fuel tank. It
should not be necessary to add any aftermarket products to your fuel
87(R+M)/2 METHOD
Maintenance and Specifications
355
2010 Navigator(nav)
Owners Guide(own2002), 1st Printing
USA(fus)