2004 Mercury Grand Marquis Specifications

Information on“T”type tires
T145/80D16 is an example of a tire
size.
Note:The temporary tire size for
your vehicle may be different than
this example.
1.T:Indicates a type of tire,
designated by the Tire and Rim
Association (T&RA), that is
intended for temporary service on
cars, SUVs, minivans and light
trucks.
2.145:Indicates the nominal width
of the tire in millimeters from
sidewall edge to sidewall edge. In
general, the larger the number, the
wider the tire.
3.80:Indicates the aspect ratio
which gives the tires ratio of height to width. Numbers of 70 or lower
indicate a short sidewall.
4.D:Indicates a“diagonal”type tire.
R:Indicates a“radial”type tire.
5.16:Indicates the wheel or rim diameter in inches. If you change your
wheel size, you will have to purchase new tires to match the new wheel
diameter.
Location of the tire label
You will find a tire label containing tire inflation pressure by tire size and
other important information located on the B-Pillar or the driver’s door.
TIRE CARE
Improper or inadequate vehicle maintenance can also cause tires to wear
abnormally. Here are some of the important maintenance items:
Tire inflation pressure
Use a tire gauge to check the tire inflation pressure, including the spare,
at least monthly and before long trips. You are strongly urged to buy a
reliable tire pressure gauge, as automatic service station gauges may be
inaccurate. Ford recommends the use of a digital or dial type tire
pressure gauge rather than a stick type tire pressure gauge.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
217

Use the recommended cold inflation pressure for optimum tire
performance and wear. Under-inflation or over-inflation may cause
uneven treadwear patterns.
Under-inflation is the most common cause of tire failures and
may result in severe tire cracking, tread separation orblowout,
with unexpected loss of vehicle control and increased risk of injury.
Under-inflation increases sidewall flexing and rolling resistance,
resulting in heat buildup and internal damage to the tire. It also may
result in unnecessary tire stress, irregular wear, loss of vehicle control
and accidents. A tire can lose up to half of its air pressure and not
appear to be flat!
When weather temperature changes occur, tire inflation pressures also
change. A 10°F(6°C) temperature change can cause a corresponding
drop of 1 psi (7 kPa) in inflation pressure. Check your tire pressures
frequently and adjust them to the proper pressure which can be found
on the tire label or certification label.
If you are checking tire pressure when the tire is hot, (i.e. driven more
than 1 mile [1.6 km]), never“bleed”or reduce air pressure. The tires are
hot from driving and it is normal for pressures to increase above
recommended cold pressures. A hot tire at or below recommended cold
inflation pressure could be significantly under-inflated.
To check the pressure in your tire(s):
1. Make sure the tires are cool, meaning they are not hot from driving
even a mile.
Note:If you have to drive a distance to get air for your tire(s), check
and record the tire pressure first and add the appropriate air pressure
when you get to the pump. It is normal for tires to heat up and the air
pressure inside to go up as you drive. Never“bleed”or reduce air
pressure when tires are hot.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve and measure the pressure.
3. Add enough air to reach the recommended air pressure
Note:If you overfill the tire, release air by pushing on the metal stem in
the center of the valve. Then recheck the pressure with your tire gauge.
4. Replace the valve cap.
5. Repeat this procedure for each tire, including the spare.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
218

Note:Some spare tires require higher inflation pressure than the other
tires. Check the tire label on the B pillar or the driver’s door for the
recommended spare tire pressure.
6. Visually inspect the tires to make sure there are no nails or other
objects embedded that could poke a hole in the tire and cause an air
leak.
7. Check the sidewalls to make sure there are no gouges, cuts or bulges.
Tire and wheel alignment
A bad jolt from hitting a curb or pothole can cause the front end of your
vehicle to become misaligned or damage to your tires. If your vehicle
seems to pull to one side when you’re driving, the wheels may be out of
alignment. Have a qualified technician at a Ford or Lincoln/Mercury
dealer check the wheel alignment periodically.
Wheel misalignment in the front or the rear can cause uneven and rapid
treadwear of your tires and should be corrected by a qualified technician
at a Ford or Lincoln/Mercury dealer. Front wheel drive (FWD) vehicles,
and those with an independent rear suspension require alignment of all
four wheels.
The tires should also be balanced periodically. An unbalanced tire and
wheel assembly may result in irregular tire wear.
Tire rotation
Rotating your tires at the recommended interval (as indicated in the
Scheduled Maintenance Guidethat comes with your vehicle) will help
your tires wear more evenly providing better tire performance and longer
tire life. Unless otherwise specified, rotate the tires approximately every
5,000 miles (8,000 km).
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
219

•Front Wheel Drive (FWD)
vehicles (front tires at top of
diagram)
•Rear Wheel Drive (RWD)
vehicles/Four Wheel Drive (4WD)
vehicles (front tires at top of
diagram)
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
220

Sometimes irregular tire wear can be corrected by rotating the tires.
Note:If your tires show uneven wear ask a qualified technician at a
Ford or Lincoln/Mercury dealership to check for and correct any wheel
misalignment, tire imbalance or mechanical problem involved before tire
rotation.
Note:Your vehicle may be equipped with a dissimilar spare tire/wheel. A
dissimilar spare tire/wheel is defined as a spare tire and/or wheel that is
different in brand, size or appearance from the road tires and wheels. If
you have a dissimilar spare tire/wheel it is intended for temporary use
only and should not be used in a tire rotation.
Note:After having your tires rotated, inflation pressure must be checked
and adjusted to the vehicle requirements.
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 you see 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
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
221

•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.
Tire Replacement Requirements
Your vehicle is equipped with tires designed to provide safe ride and
handling capability.
Only use replacement tires and wheels that are the same size
and type (such as P-metric versus LT-metric or all-season versus
all-terrain) as those originally provided by Ford. Use of any tire or
wheel not recommended by Ford can affect the safety and
performance of your vehicle, which could result in an increased risk of
loss of vehicle control, vehicle rollover, personal injury and death.
Additionally the use of non-recommended tires and wheels could cause
steering, suspension, axle or transfer case/power transfer unit failure. If
you have questions regarding tire replacement, see an authorized Ford
or Lincoln/Mercury dealer.
Make sure all tires and wheels on the vehicle are of the same size, type,
tread design, brand, load-carrying capacity and speed rating because it
can affect the safety and performance of your vehicle, which could result
in an increased risk of loss of vehicle control, vehicle rollover, personal
injury and death.
You should replace the spare tire when you replace the other road tires
due to the aging of the spare tire.
Safety practices
Driving habits have a great deal to do with your tire mileage and safety.
•Observe posted speed limits
•Avoid fast starts, stops and turns
•Avoid potholes and objects on the road
•Do not run over curbs or hit the tire against a curb when parking
If your vehicle is stuck in snow, mud, sand, etc.,do notrapidly spin the
tires; spinning the tires can tear the tire and cause an explosion. A tire
can explode in as little as three to five seconds.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
222

Tire explosions can cause death, personal injury or property
damage. Do not allow anyone to stand near, directly ahead or
behind the spinning tire.
Never spin the tires in excess of the 35 mph (55 km/h) point
indicated on the speedometer.
Highway hazards
No matter how carefully you drive there’s always the possibility that you
may eventually have a flat tire on the highway. Drive slowly to the
closest safe area out of traffic. This may further damage the flat tire, but
your safety is more important.
If you feel a sudden vibration or ride disturbance while driving, or you
suspect your tire or vehicle has been damaged, immediately reduce your
speed. Drive with caution until you can safely pull off the road. Stop and
inspect the tires for damage. If a tire is under-inflated or damaged,
deflate it, remove wheel and replace it with your spare tire and wheel. If
you cannot detect a cause, have the vehicle towed to the nearest repair
facility or tire dealer to have the vehicle inspected.
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:
•Either cable type chains or SAE class S chains can be used.
•Install chains securely, verifying that the chains do not touch any
wiring, brake lines or fuel lines.
•Drive cautiously. If you hear the chains rub or bang against your
vehicle, stop and re-tighten the chains. If this does not work, remove
the chains to prevent damage to your vehicle.
•If possible, avoid fully loading your vehicle.
•Remove the tire chains when they are no longer needed. Do not use
tire chains on dry roads.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
223

•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
MOTORCRAFT PART NUMBERS
Component 4.6L SOHC V8 engine
Air filter element FA-1668
Fuel filter FG-986B
Battery-standard BXT-65–650
Battery-heavy duty BXT-65–750
Oil filter FL-820-S
PCV valve
1
Spark plugs2
1
The PCV valve is a critical emission component. It is one of the items
listed in theScheduled Maintenance Guideand is essential to the life
and performance of your vehicle and to its emissions system.
For PCV valve replacement, see your dealer or a qualified service
technician. Refer to theScheduled Maintenance Guidefor the
appropriate intervals for changing the PCV valve.
Replace the PCV valve with one that meets Ford material and
design specifications for your vehicle, such as a Motorcraft or
equivalent replacement part. The customer warranty may be void
for any damage to the emissions system if such a PCV valve is not
used.
2For spark plug replacement, see your dealer or a qualified service
technician. Refer to theScheduled Maintenance Guidefor the
appropriate intervals for changing the spark plugs.
Replace the spark plugs with ones that meet Ford material and
design specifications for your vehicle, such as Motorcraft or
equivalent replacement parts. The customer warranty may be
void for any damage to the engine if such spark plugs are not
used.
Refer to Vehicle Emissions Control Information (VECI) decal for spark
plug gap information.
2004 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
224