
12.Treadwear, Traction and Temperature Grades
•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 graded 150
would wear one and one-half (1
1 2) times as well on the government
course as a tire graded 100.
•Traction:The traction grades, from highest to lowest are AA, A, B,
and C. The grades represent the tire’s ability to stop on wet pavement
as measured under controlled conditions on specified government test
surfaces of asphalt and concrete. A tire marked C may have poor
traction performance.
•Temperature: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.
13.Maximum Permissible Inflation Pressure:Indicates the tire
manufacturers’ maximum permissible pressure and/or the pressure at
which the maximum load can be carried by the tire. This pressure is
normally higher than the manufacturer’s recommended cold inflation
pressure which can be found on either the Safety Compliance
Certification Label which is located on the B-Pillar or the edge of the
driver’s door. The cold inflation pressure should never be set lower than
the recommended pressure on the vehicle label.
The tire suppliers may have additional markings, notes or warnings such
as standard load, radial tubeless, etc.
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Tires, Wheels and Loading
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TIRE CARE
Improper or inadequate vehicle maintenance can also cause tires to wear
abnormally. Here are some of the important maintenance items:
Tire wear
Measure and inspect the tire tread on all your tires periodically.
Advanced and unusual tire wear can reduce the ability of tread to grip
the road in adverse (wet, snowy, etc.) conditions. Visually check your
tires for uneven wear, looking for high and low areas or unusually
smooth areas. Also check for signs of tire damage.
When the tread is worn down to
1/16th of an inch (2 mm), tires must
be replaced to prevent your vehicle
from skidding and hydroplaning.
Built-in treadwear indicators, or
“wear bars”, which look like narrow
strips of smooth rubber across the
tread will appear on the tire when
the tread is worn down to 1/16th of
an inch (2 mm). When the tire tread
wears down to the same height as
these “wear bars”, the tire is worn
out and should be replaced.
Inspect your tires frequently for any
of the following conditions and
replace them if one or more of the
following conditions exist:
•Fabric showing through the tire
rubber
•Bulges in the tread or sidewalls
•Cracks or cuts on the sidewalls
•Cracks in the tread groove
•Impact damage resulting from use
•Separation in the tread
•Separation in the sidewall
•Severe abrasion on the sidewall
If your vehicle has a leak in the exhaust system, a road tire or the spare
tire may be exposed to hot exhaust temperatures requiring the tire to be
replaced.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
149

STARTING
Positions of the ignition
1. OFF/LOCK, shuts off the engine
and all accessories/locks the
gearshift lever and allows key
removal.
2. ACC, allows the electrical
accessories such as the radio to
operate while the engine is not
running.
3. ON, all electrical circuits
operational. Warning lights
illuminated. Key position when driving.
4. START, cranks the engine. Release the key as soon as the engine
starts.
Preparing to start your vehicle
Engine starting is controlled by the powertrain control system. This
system meets all Canadian Interference-Causing Equipment standard
requirements regulating the impulse electrical field strength of radio
noise.
When starting a fuel-injected engine, avoid pressing the accelerator
before or during starting. Only use the accelerator when you have
difficulty starting the engine. For more information on starting the
vehicle, refer toStarting the enginein this chapter.
Extended idling at high engine speeds can produce very high
temperatures in the engine and exhaust system, creating the risk
of fire or other damage.
Do not park, idle, or drive your vehicle in dry grass or other dry
ground cover. The emission system heats up the engine
compartment and exhaust system, which can start a fire.
Do not start your vehicle in a closed garage or in other enclosed
areas. Exhaust fumes can be toxic. Always open the garage door
before you start the engine. SeeGuarding against exhaust fumesin
this chapter for more instructions.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
163

Starting the engine
1. Turn the key to 3 (ON) without
turning the key to 4 (START).
2. Turn the key to 4 (START), then
release the key as soon as the
engine starts. Excessive cranking
could damage the starter.
Note:If the engine does not start within five seconds on the first try,
turn the key to OFF, wait 10 seconds and try again. If the engine still
fails to start, press the accelerator to the floor and try again; this will
allow the engine to crank with the fuel shut off in case the engine is
flooded with fuel.
Using the engine block heater (if equipped)
Use of an engine block heater is strongly recommended if you live in a
region where temperatures reach -10°F (-23°C) or below. For best
results, plug the heater in at least three hours before starting the vehicle.
The heater can be plugged in the night before starting the vehicle.
To reduce the risk of electrical shock, do not use your heater
with ungrounded electrical systems or two-pronged (cheater)
adapters.
Guarding against exhaust fumes
Carbon monoxide is present in exhaust fumes. Take precautions to avoid
its dangerous effects.
If you smell exhaust fumes inside your vehicle, have your dealer
inspect your vehicle immediately. Do not drive if you smell
exhaust fumes.
Important ventilating information
If the engine is idling while the vehicle is stopped for a long period of
time, open the windows at least one inch (2.5 cm) or adjust the heating
or air conditioning to bring in fresh air.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
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2 (Second)
This position allows for second gear only.
•Provides engine braking.
•Use to start-up on slippery roads.
•To return to
(Overdrive), move the gearshift lever into the
(Overdrive) position.
•Selecting 2 (Second) at higher speeds will cause the transmission to
downshift to second gear at the appropriate vehicle speed.
1 (First)
•Provides maximum engine braking.
•Allows upshifts by moving gearshift lever.
•Will not downshift into 1 (First) at high speeds; allows for 1 (First)
when vehicle reaches slower speeds.
Forced downshifts
•Allowed in
(Overdrive) or Drive.
•Depress the accelerator to the floor.
•Allows transmission to select an appropriate gear.
If your vehicle gets stuck in mud or snow
If your vehicle gets stuck in mud or snow, it may be rocked out by
shifting between forward and reverse gears, stopping between shifts in a
steady pattern. Press lightly on the accelerator in each gear.
Do not rock the vehicle if the engine is not at normal operating
temperature or damage to the transmission may occur.
Do not rock the vehicle for more than a minute or damage to the
transmission and tires may occur, or the engine may overheat.
TRACTION-LOKAXLE (IF EQUIPPED)
This axle provides added traction on slippery surfaces, particularly when
one wheel is on a poor traction surface. Under normal conditions, the
Traction-Lokaxle functions like a standard rear axle.
Extended use of other than the manufacturer’s specified size tires on a
Traction-Lokrear axle could result in a permanent reduction in
effectiveness. This loss of effectiveness does not affect normal driving
and should not be noticeable to the driver.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
178

The fuses are coded as follows.
Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse
Panel Description
1 15A Cluster, Lighting Control Module
(Interior Lighting)
2 10A Ignition (ON) - Electronic
Automatic Temperature Control
(EATC) module, A/C mode switch
(vehicles equipped with EATC)
3 10A EATC module
4 10A Ignition (ON) - Anti-lock Brake
System (ABS) module, Positive
Crankcase Ventilation (PCV)
5 10A Speed control deactivation switch,
Stop signal, Brake-Transmission
Shift Interlock (BTSI)
(column-shift transmission)
6 10A Ignition (ON) - Cluster
7 10A LCM (Park lamps, Switch
illumination)
27 25
26 2423 21
2219
20
18 16
17 1514 12
1310
33
31
2932
30
28 11
97
8653
41
2Relay
1
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Owners Guide (post-2002-fmt)
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Roadside Emergencies
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5. Power steering fluid reservoir
6. Engine coolant reservoir
7. Battery
8. Power distribution box
9. Engine oil filler cap
10. Automatic transmission fluid dipstick
WINDSHIELD WASHER FLUID
Add fluid to fill the reservoir if the
level is low. In very cold weather, do
not fill the reservoir completely.
Only use a washer fluid that meets
Ford specification WSB-M8B16–A2.
Refer toLubricant specifications
in this chapter.
State or local regulations on volatile organic compounds may restrict the
use of methanol, a common windshield washer antifreeze additive.
Washer fluids containing non-methanol antifreeze agents should be used
only if they provide cold weather protection without damaging the
vehicle’s paint finish, wiper blades or washer system.
If you operate your vehicle in temperatures below 40° F (4.5°C),
use washer fluid with antifreeze protection. Failure to use
washer fluid with antifreeze protection in cold weather could result in
impaired windshield vision and increase the risk of injury or accident.
Note:Do not put washer fluid in the engine coolant reservoir. Washer
fluid placed in the cooling system may harm engine and cooling system
components.
ENGINE OIL
Checking the engine oil
Refer to thescheduled maintenance informationfor the appropriate
intervals for checking the engine oil.
1. Make sure the vehicle is on level ground.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
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BATTERY
Your vehicle is equipped with a
Motorcraft maintenance-free battery
which normally does not require
additional water during its life of
service.
However, for severe usage or in high temperature climates, check the
battery electrolyte level. Refer toscheduled maintenance information
for the service interval schedules.
Keep the electrolyte level in each cell up to the “level indicator”.
Do not overfill the battery cells.
If the electrolyte level in the battery is low, you can add plain tap water
to the battery, as long as you do not use hard water (water with a high
mineral or alkali content). If possible, however, try to only fill the battery
cells with distilled water. If the battery needs water often, have the
charging system checked.
If your battery has a cover/shield, make sure it is reinstalled
after the battery has been cleaned or replaced.
For longer, trouble-free operation, keep the top of the battery clean and
dry. Also, make certain the battery cables are always tightly fastened to
the battery terminals.
If you see any corrosion on the battery or terminals, remove the cables
from the terminals and clean with a wire brush. You can neutralize the
acid with a solution of baking soda and water.
Batteries normally produce explosive gases which can cause
personal injury. Therefore, do not allow flames, sparks or lighted
substances to come near the battery. When working near the battery,
always shield your face and protect your eyes. Always provide proper
ventilation.
2005 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Maintenance and Specifications
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