Page 15 of 368

Trip odometer: Registers the
kilometers (miles) of individual
journeys. Press and release the
message center INFO button until
“ TRIP ” appears in the display (this
represents the trip mode). Press
and hold the RESET button for
three seconds to reset.
Tachometer: Indicates the engine
speed in revolutions per minute.
Driving with your tachometer
pointer continuously at the top of
the scale may damage the engine.
Fuel gauge: Indicates
approximately how much fuel is left
in the fuel tank (when the ignition
is in the ON position). The fuel
gauge may vary slightly when the
vehicle is in motion or on a grade.
The ignition should be in the OFF
position while the vehicle is being
refueled. When the gauge first
indicates empty, there is a small amount of reserve fuel in the tank.
When refueling the vehicle from empty indication, the amount of fuel
that can be added will be less than the advertised capacity due to the
reserve fuel.
The FUEL icon and arrow indicates which side of the vehicle the fuel
filler door is located.
Refer to Filling the tank in the Maintenance and Specifications
chapter for more information.
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
USA English (fus) Instrument Cluster
15
Page 323 of 368

If you have run out of fuel:
• You may need to cycle the ignition from OFF to ON several times after
refueling, to allow the fuel system to pump the fuel from the tank to
the engine.
• Your “ Service Engine Soon ” indicator may come on. For more
information on the “ Service Engine Soon ” indicator, refer to the
Instrument cluster chapter.
Fuel Filter
For fuel filter replacement, see your dealer or a qualified service
technician. Refer to the scheduled maintenance guide for the appropriate
intervals for changing the fuel filter.
Replace the fuel filter with an authorized Motorcraft part. The
customer warranty may be void for any damage to the fuel system
if an authorized Motorcraft fuel filter is not used.
ESSENTIALS OF GOOD FUEL ECONOMY
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1,600 km (1,000
miles) of driving (engine break-in period). You will get a more accurate
measurement after 3,000 km – 5,000 km (2,000 miles-3,000 miles).
Filling the tank
The advertised fuel capacity of the fuel tank on your vehicle is equal to
the rated refill capacity of the fuel tank as listed in the Refill capacities
section of this chapter.
The advertised capacity is the amount of the indicated capacity and the
empty reserve combined. Indicated capacity is the difference in the
amount of fuel in a full tank and a tank when the fuel gauge indicates
empty. Empty reserve is the small amount of fuel remaining in the fuel
tank after the fuel gauge indicates empty.
The amount of usable fuel in the empty reserve varies and should
not be relied upon to increase driving range. When refueling your
vehicle after the fuel gauge indicates empty, you might not be
able to refuel the full amount of the advertised capacity of the
fuel tank due to the empty reserve still present in the tank.
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
USA English (fus) Maintenance and Specifications
323
Page 349 of 368

Component 5.4L 4V V8 engine
Spark plugs* AGSF-32PM
* Refer to Vehicle Emissions Control Information (VECI) decal for spark
plug gap information.
REFILL CAPACITIES
Fluid Ford Part
Name Application Capacity
Brake fluid Motorcraft High
Performance
DOT 3 Motor
Vehicle Brake
Fluid All Fill to line on
reservoir
Engine oil
(includes filter
change) 6
Motorcraft SAE
5W-20 Premium
Synthetic Blend
Motor Oil (US)
Motorcraft SAE
5W-20 Super
Premium Motor
Oil (Canada) All 6.6L (7.0
quarts)
Fuel tank N/A All 106 L (28
gallons)
Power steering
fluid Motorcraft
MERCON AT F All Fill to line on
reservoir
Transmission
fluid 1
Motorcraft
MERCON AT F 4 x 2 vehicles 15.0L (15.9
quarts) 2
4 x 4 vehicles 15.5L (16.4
quarts) 2
Transfer case
fluid Motorcraft
MERCON AT F 4 x 4 vehicles 1.9L (2.0
quarts)
Engine coolant 3
Motorcraft
Premium Gold
Engine Coolant
(yellow-colored) without aux rear
heat 21.0L (22.2
quarts)
with aux rear
heat 23.0L (24.3
quarts)
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
USA English (fus) Maintenance and Specifications
349
Page 351 of 368

an automatic transmission application requiring MERCON may
cause transmission damage. Use of any fluid other than the
recommended fluid may cause transmission damage. 2
Indicates only approximate dry-fill capacity. Some applications may vary
based on cooler size and if equipped with an in-tank cooler. The amount
of transmission fluid and fluid level should be set by the indication on
the dipstick ’ s normal operating range.3
Add the coolant type originally equipped in your vehicle. 4
Your vehicle ’ s rear axle is filled with a synthetic rear axle lubricant and
is considered lubricated for life. These lubricants are not to be checked
or changed unless a leak is suspected, service is required or the axle has
been submerged in water. The axle lubricant should be changed any time
the axle has been submerged in water.
Service refill capacities are determined by filling the rear axle 23mm (0.9
inch) below the bottom of the filler hole. 5
Add 118 ml (4 oz.) of Additive Friction Modifier XL-3 or equivalent
meeting Ford specification EST-M2C118 – A for complete refill of Limited
Slip axles. For complete refills, fill using the Additive Friction Modifier
first. 6
Use of synthetic or synthetic blend motor oil is not mandatory. Engine
oil need only meet the requirements of Ford specification
WSS-M2C153 – H and the API Certification mark.
LUBRICANT SPECIFICATIONS
Item Ford part
name Ford part
number Ford
specification
Hinges, latches,
striker plates
and rotors, seat
tracks, fuel filler
door hinge and
spring Multi-Purpose
Grease XG-4 or XL-5 ESR-M1C159-A
or ESB-M1C93-B
Lock cylinders Penetrating and
Lock Lubricant Motorcraft XL-1 ESB-M2C75-B
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
USA English (fus) Maintenance and Specifications
351