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How fail-safe cooling works
If the engine begins to overheat:
• The engine coolant temperature
gauge will move to the red (hot)
area.
• The and the symbol
will illuminate.
• The “ Service Engine Soon ”
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 a service facility 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 a service facility.
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.
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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.
BRAKE FLUID RESERVOIR
The fluid level will drop slowly as
the brakes wear, and will rise when
the brake components are replaced.
Fluid levels between the “ MIN ” and
“ MAX ” lines are within the normal
operating range, there is no need to
add fluid. If the fluid levels are
outside of the normal operating range, the performance of your brake
system could be compromised, seek service from your dealer
immediately. MAX
MIN
MAX
MIN
MAX
MIN
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
USA English (fus) Maintenance and Specifications
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Page 352 of 368

Item Ford part
name Ford part
number Ford
specification
Brake fluid Motorcraft High
Performance
DOT 3 Motor
Vehicle Brake
Fluid PM-1 ESA-M6C25-A
and DOT 3
Driveshaft, slip
spline, double
Cardan joint
center ball Premium Long
Life Grease XG-1-C or
XG-1-K ESA-M1C75 – B
Engine coolant Motorcraft
Premium Gold
Engine Coolant
(yellow-colored) VC-7 – A WSS-M97B51-A1
Engine oil Motorcraft SAE
5W-20 Premium
Synthetic Blend
Motor Oil
Motorcraft SAE
5W-20 Super
Premium Motor
Oil (Canada) XO-5W20-QSP
(US)
CXO-5W20 – LSP12
(Canada) WSS-M2C153-H
and API
Certification Mark
4x4 front wheel
bearings, 4x4
spindle needle
bearings, spindle
thrust bearings
& front drive
axle u-joint/slip
spline High
Temperature
4x4 Front Axle
& Wheel Bearing
Grease E8TZ-19590-A ESA-M1C198-A
Automatic
transmission 1
Motorcraft
MERCON AT F XT-2-QDX MERCON
Power steering
fluid Motorcraft
MERCON AT F XT-2-QDX MERCON
2004 Navigator (nav)
Owners Guide (post-2002-fmt)
USA English (fus)Maintenance and Specifications
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