1998 FORD EXPEDITION Owners Manual

cleaning them, and apply a small
quantity of grease to the top of
each battery terminal to help
prevent corrosion.
If your battery has a
cover/shield, make sure it is
reinstalled after the battery is
replaced.
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 conditions before your
vehicle will drive properly. To
begin this process:
1. Put the gearshift in P (Park),
turn off all accessories and start
the vehicle.
2. Let the engine idle for at least
one minute.
3. The relearning process will
automatically complete as you
drive the vehicle.
²If you do not allow the engine to
relearn its idle, the idle quality
of your vehicle may be adversely
affected until the idle is
eventually relearned.
²If the battery has been
disconnected or a new battery
has been installed, the clock and
the preset radio stations must
be reset once the battery is
reconnected.
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169

²Always dispose of automotive
batteries in a responsible
manner. Follow your
communities standards for
disposal. Call your local
recycling center to find out
more about recycling automotive
batteries.
AIR CLEANER FILTER
MAINTENANCE
Refer to the ªService Guideº for
the appropriate intervals for
changing the air cleaner filter.
Do not start your engine
with the air cleaner
removed and do not remove it
while the engine is running.
CHANGING THE AIR FILTER
1. Loosen the clamp that secures
the air cleaner in place.
2. Separate the two halves of the
air cleaner.
3. Remove the air filter element
from the open end of the engine
air cleaner and replace it with a
new element. Be careful not to
crimp the filter edges between
halves. This could cause filter
damage if not properly seated.
4. Replace the two halves of the
air cleaner and secure the clamp.
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170

For information on replacement air
filter elements, refer to the
Capacities and specifications
chapter.
WINDSHIELD WIPER BLADES
Check the wiper blades at least
twice a year or when they seem
less effective. Substances such as
tree sap and some hot wax
treatments used by commercial car
washes reduce the effectiveness of
wiper blades.
Checking the wiper blades
If the wiper blades do not wipe
properly, clean both the windshield
and wiper blades using undiluted
windshield wiper solution or a mild
detergent. Rinse thoroughly with
clean water. To avoid damaging the
blades, do not use fuel, kerosene,
paint thinner or other solvents.
Changing the wiper blades
When replacing wiper blade
assemblies, always use a
Motorcraft part or equivalent. To
make replacing the wipers easy,
turn the ignition to ACC, then turn
the wipers on. When the wipers
reach the vertical position, turn
the ignition to LOCK.
To replace the wiper blades:
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171

1. Pull the wiper arm away from
the windshield and lock into the
service position.
2. Turn the blade at an angle from
the wiper arm. Push the lock pin
with a screwdriver to release the
blade and pull the wiper blade
down toward the windshield to
remove it from the arm.
3. Attach the new wiper to the
wiper arm and press it into place
until a click is heard.
INFORMATION ABOUT TIRE
QUALITY GRADES
New vehicles are fitted with tires
that have their Tire Quality Grade
(described below) molded into the
tire's sidewall. These Tire Quality
Grades are determined by
standards that the United States
Department of Transportation has
set.
Tire Quality Grades apply to new
pneumatic tires for use on
passenger cars. They do not apply
to deep tread, winter-type snow
tires, space-saver or temporary use
spare tires, tires with nominal rim
diameters of 10 to 12 inches or
limited production tires as defined
in Title 49 Code of Federal
Regulations Part 575.104(c)(2).
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172

U.S. Department of
Transportation-Tire quality
grades:The U.S. Department of
Transportation requires Ford to
give you the following information
about tire grades exactly as the
government has written it.
Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on a
specified government test course.
For example, a tire grade 150
would wear one and one-half
(1 1/2) times as well on the
government course as a tire grade
100. The relative performance of
tires depends upon the actual
conditions of their use, however,
and may depart significantly from
the norm due to variations in
driving habits, service practices,
and differences in road
characteristics and climate.
Traction A B C
The traction grades, from highest
to lowest are A, B, and C, and they
represent the tire's ability to stop
on wet pavement as measured
under test surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
The traction grade
assigned to this tire is
based on braking (straight
ahead) traction tests and does
not include cornering (turning)
traction.
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173

Temperature A B C
The temperature grades are A (the
highest), B, and C, representing
the tire's resistance to the
generation of heat and its ability to
dissipate heat when tested under
controlled conditions on a
specified indoor laboratory test
wheel. Sustained high temperature
can cause the material of the tire
to degenerate and reduce tire life,
and excessive temperature can
lead to sudden tire failure. The
grade C corresponds to a level of
performance which all passenger
car tires must meet under the
Federal Motor Vehicle Safety
Standard No. 109. Grades B and A
represent higher levels of
performance on the laboratory test
wheel than the minimum required
by law.
The temperature grade for
this tire is established for a
tire that is properly inflated and
not overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
SERVICING YOUR TIRES
Checking the tire pressure
²Use an accurate tire pressure
gauge.
²Check the tire pressure when
tires are cold, after the vehicle
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174

has been parked for at least one
hour or has been driven less
than 5 km (3 miles).
²Adjust tire pressure to
recommended specifications
found on the Safety Compliance
Certification Label.
Improperly inflated tires
can affect vehicle handling
and can fail suddenly, possibly
resulting in loss of vehicle
control.
Tire rotation
Because your vehicle's tires
perform different jobs, they often
wear differently. To make sure
your tires wear evenly and last
longer, rotate them as indicated in
the ªService Guide.º If you notice
that the tires wear unevenly, have
them checked.
²Four tire rotation
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175

Replacing the tires
Replace the tires when the wear
band is visible through the tire
treads.
Failure to follow these
precautions may adversely
affect the handling of the vehicle
and make it easier to lose control
and roll over.
Tires that are larger or smaller
than your vehicle's original tires
may also affect the accuracy of
your speedometer.
SNOW TIRES AND CHAINS
Snow tires must be the
same size and grade as the
tires you currently have on your
vehicle.
The tires on your vehicle have all
weather treads to provide traction
in rain and snow. However, in some
climates, you may need to use
snow tires and chains.
Follow these guidelines when using
snow tires and chains:
²Use only cable type chains
offered by Ford as an accessory
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176