
How fail-safe cooling works
If the engine begins to overheat:
•The engine coolant temperature gauge will move to the red (hot)
area.
•The
symbol will illuminate.
•The
indicator light will illuminate.
If the engine reaches a preset over-temperature condition, the engine
will automatically switch to alternating cylinder operation. Each disabled
cylinder acts as an air pump and cools the engine.
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.
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.
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Maintenance and Specifications
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The OBD-II system is designed to check the emission control system
during normal driving. A complete check may take several days. If the
vehicle is not ready for I/M testing, the following driving cycle consisting
of mixed city and highway driving may be performed:
15 minutes of steady driving on an expressway/highway followed by 20
minutes of stop-and-go driving with at least four 30-second idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete. If
the vehicle is still not ready for I/M testing, the above driving cycle will
have to be repeated.
POWER STEERING FLUID
Check the power steering fluid. Refer to thescheduled maintenance
informationfor the service interval schedules.
1. Start the engine and let it run
until it reaches normal operating
temperature (the engine coolant
temperature gauge indicator will be
near the center of the normal area
between H and C).
2. While the engine idles, turn the
steering wheel left and right several
times.
3. Turn the engine off.
4. Check the fluid level in the reservoir. It should be between the MIN
and MAX lines. Do not add fluid if the level is in this range.
5. If the fluid is low, add fluid in small amounts, continuously checking
the level until it reaches the range between the MIN and MAX lines. Be
sure to put the cap back on the reservoir. Refer toMaintenance
product specifications and capacitiesin this chapter for the proper
fluid type.
2008 Navigator(nav)
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Maintenance and Specifications
334

Item Capacity Ford part nameFord part number /
Ford specification
Cooling system stop
leak pellets—Motorcraft Cooling
System Stop Leak PelletsVC-6 /
WSS-M99B37-B6
Engine oil 7.0 quarts (6.6 L)Motorcraft SAE 5W-20
Premium Synthetic
Blend Motor Oil
Motorcraft SAE 5W-20
Super Premium Motor
Oil
2
XO-5W20-QSP (US)
CXO-5W20- LSP12
(Canada) /
WSS-M2C930-A and API
Certification Mark
Automatic transmission
fluid
(6HP26)11.0 quarts
(10.5L)
3
Motorcraft MERCONSP
AT F
4
XT-6-QSP /
MERCONSP
Power steering fluidFill between MIN
and MAX lines on
reservoirMotorcraft MERCONV
AT FXT-5-QM /
MERCONV
Front axle fluid (4X4) 3.5 pints (1.8 L)Motorcraft SAE 80W-90
Premium Rear Axle LubeXY-80W90-QL /
WSP-M2C197-A
Rear axle
fluid–Conventional
differential
(9.75 inch axle)4.5 pints (2.13L)Motorcraft SAE 75W-140
Synthetic Rear Axle
Lube
5
XY-75W140-QL /
WSL-M2C192-A
Transfer case fluid
(4X4)1.6-1.8 quarts
(1.5-1.7L)Motorcraft Transfer Case
FluidXL–12 /
—
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Maintenance and Specifications
340

waxing .....................................302
wheels ......................................302
wiper blades ............................304
Clock ............................................88
Compass, electronic
set zone adjustment ...............107
Console ........................................87
overhead ..............................86–87
Controls
power seat ...............................143
steering column ........................99
Coolant
checking and adding ..............317
refill capacities ................320, 339
specifications ..........................339
Cruise control
(see Speed control) ....................96
Customer Assistance ................265
Ford Extended Service
Plan ..........................................297
Getting assistance outside the
U.S. and Canada .....................298
Getting roadside assistance ...265
Getting the service
you need .................................293
Ordering additional owner’s
literature .................................299
Utilizing the
Mediation/Arbitration
Program ...................................297
D
Daytime running lamps
(see Lamps) ................................73
Defrost
rear window ..............................71Dipstick
automatic transmission
fluid ..........................................335
engine oil .................................312
Driving under special
conditions ..................250, 259, 262
sand .........................................261
snow and ice ...........................263
through water .................261, 264
DVD system .................................35
E
Electronic message center .......106
Emergencies, roadside
jump-starting ..........................284
Emission control system ..........331
Engine ........................................342
cleaning ...................................303
coolant .....................................317
fail-safe cooling .......................321
idle speed control ...................315
lubrication specifications .......339
refill capacities ........................339
service points ..........................309
starting after a collision .........267
Engine block heater .................235
Engine oil ..................................312
change oil soon warning,
message center .......................312
checking and adding ..............312
dipstick ....................................312
filter, specifications ........314, 338
recommendations ...................314
refill capacities ........................339
specifications ..........................339
Event data recording ....................7
Exhaust fumes ..........................235
F
Fail safe cooling ........................321
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Index
348

L
Lamps
autolamp system .......................72
bulb replacement
specifications chart ..................77
daytime running light ...............73
fog lamps ...................................72
headlamps .................................72
headlamps, flash to pass ..........73
interior lamps .....................76, 78
replacing bulbs .........................81
Lane change indicator
(see Turn signal) ........................75
Liftgate ..............119, 122, 130–131
Lights, warning and indicator ....12
anti-lock brakes (ABS) ..........238
Load limits .................................217
Loading instructions .................223
Locks
autolock ...................................124
childproof ................................128
doors ........................................124
Lubricant specifications ...........339
Lug nuts ....................................283
Luggage rack .............................123
Lumbar support, seats .............142
M
Message center .........................106
english/metric button .............113
system check button ..............114
warning messages ...................114
Mirrors ...................................91–92
automatic dimming rearview
mirror ........................................92
fold away ...................................93heated ........................................93
programmable memory ..........132
signal .........................................94
Moon roof ..................................101
Motorcraft parts ........306, 323, 338
N
Navigation system .......................64
O
Octane rating ............................327
Oil (see Engine oil) ..................312
P
Panic alarm feature, remote
entry system ..............................131
Parking brake ............................239
Parts (see Motorcraft parts) ....338
Pedals (see Power adjustable
foot pedals) .................................94
Power adjustable foot pedals .....94
Power deployable running
boards ..........................................94
Power distribution box
(see Fuses) .......................269, 271
Power door locks ......................124
Power liftgate ............................119
Power mirrors .............................92
Power point .................................88
Power steering ..................244–245
fluid, checking and adding ....334
fluid, refill capacity ................339
fluid, specifications .................339
Power Windows ...........................89
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Index
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Preparing to drive your
vehicle ........................................246
R
Radio ............................................20
Rear seat entertainment
system ..........................................35
Rear video camera ....................254
Rear window defroster ...............71
Relays ........................................268
Remote entry system ...............128
illuminated entry ....................135
locking/unlocking
doors ................................128–129
opening the trunk ...........130–131
panic alarm .............................131
replacement/additional
transmitters .............................134
replacing the batteries ...........133
Reverse sensing system ...........251
Roadside assistance ..................265
Roll stability control .................240
Roof rack ...................................123
S
Safety Belt Maintenance ..........166
Safety belts (see Safety
restraints) ..157, 159–160, 162–164
Safety Canopy ...................175, 177
Safety defects, reporting ..299–300
Safety
restraints ...157, 159–160, 162–164
Belt-Minder...........................167
extension assembly ................165
for adults .................160, 162–163
for children .....................180–181safety belt maintenance .........166
warning light and
chime ...............................166–167
Safety seats for children ..........184
Safety Compliance
Certification Label ....................343
Satellite Radio Information ........33
Seats ..........................................142
child safety seats ....................184
climate control ........................146
memory seat ...................132, 145
SecuriLock passive anti-theft
system ................................138–140
Servicing your vehicle ..............308
Snowplowing .................................7
Spark plugs,
specifications .....................338, 342
Special notice
utility-type vehicles ....................8
Specification chart,
lubricants ...................................339
Speed control ..............................96
Stability system .........................240
Starting your vehicle ........232–234
jump starting ..........................284
Steering wheel
controls ......................................99
tilting .........................................84
T
Tire Pressure Monitoring
System (TPMS)
Driving .....................................261
Tires, Wheels and Loading ....212
Warning Displays ..............12, 114
Tires ...........................197–198, 275
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Index
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