2008 Mercury Grand Marquis maintenance

Front safety belt height adjustment
Your vehicle has safety belt height
adjustments for the driver and front
outboard passenger. Adjust the
height of the shoulder belt so the
belt rests across the middle of your
shoulder.
To lower the shoulder belt height,
push the button and slide the height
adjuster down. To raise the height
of the shoulder belt, push the
button and slide the height adjuster
up. Pull down on the height adjuster to make sure it is locked in place.
Position the safety belt height adjusters so that the belt rests
across the middle of your shoulder. Failure to adjust the safety
belt properly could reduce the effectiveness of the seat belt and
increase the risk of injury in a collision.
Safety belt maintenance
Inspect the safety belt systems periodically to make sure they work
properly and are not damaged. Inspect the safety belts to make sure
there are no nicks, tears or cuts. Replace if necessary. All safety belt
assemblies, including retractors, buckles, front safety belt buckle
assemblies, buckle support assemblies (slide bar-if equipped), shoulder
belt height adjusters (if equipped), shoulder belt guide on seatback (if
equipped), child safety seat LATCH and tether anchors, and attaching
hardware, should be inspected after a collision. Ford Motor Company
recommends that all safety belt assemblies in use in vehicles involved in
a collision be replaced. However, if the collision was minor and an
authorized dealer finds that the belts do not show damage and continue
to operate properly, they do not need to be replaced. Safety belt
assemblies not in use during a collision should also be inspected and
replaced if either damage or improper operation is noted.
Failure to inspect and if necessary replace the safety belt
assembly under the above conditions could result in severe
personal injuries in the event of a collision.
For proper care of soiled safety belts, refer toInteriorin theCleaning
chapter.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
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An out of position front center occupant could affect the
decision of the front passenger sensing system.
If it is necessary to modify an advanced front airbag system to
accommodate a person with disabilities, contact the Ford Customer
Relationship Center at the phone number shown in theCustomer
Assistancesection of thisOwner’s Guide.
Any alteration/modification to the front passenger seat may
affect the performance of the front passenger sensing system.
Determining if the system is operational
The SRS uses a readiness light in the instrument cluster or a tone to
indicate the condition of the system. Refer toAirbag readinesssection
in theInstrument Clusterchapter. Routine maintenance of the airbag is
not required.
A difficulty with the system is indicated by one or more of the following:
•The readiness light will either
flash or stay lit.
•The readiness light will not
illuminate immediately after
ignition is turned on.
•A series of five beeps will be heard. The tone pattern will repeat
periodically until the problem and/or light are repaired.
If any of these things happen, even intermittently, have the SRS serviced
at an authorized dealer immediately. Unless serviced, the system may not
function properly in the event of a collision.
Seat-mounted side airbag system (if equipped)
Do not place objects or mount equipment on or near the airbag
cover on the side of the seatbacks of the front seats or in front
seat areas that may come into contact with a deploying airbag. Failure
to follow these instructions may increase the risk of personal injury in
the event of a collision.
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The side airbags are fitted on the outboard side of the seatbacks of the
front seats. In certain lateral collisions, the airbag on the side affected by
the collision will be inflated. The airbag was designed to inflate between
the door panel and occupant to further enhance the protection provided
occupants in side impact collisions.
The airbag SRS is designed to activate when the vehicle sustains lateral
deceleration sufficient to cause the sensors to close an electrical circuit
that initiates airbag inflation.
The fact that the airbags did not inflate in a collision does not mean that
something is wrong with the system. Rather, it means the forces were
not of the type sufficient to cause activation. Side airbags are designed
to inflate in side-impact collisions, not roll-over, rear-impact, frontal or
near-frontal collisions, unless the collision causes sufficient lateral
deceleration.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the side airbag has
deployed,the airbag will
not function again. The side
airbag system (including the
seat) must be inspected and
serviced by an authorized
dealer.If the airbag is not
replaced, the unrepaired area will
increase the risk of injury in a
collision.
Determining if the system is operational
The SRS uses a readiness light in the instrument cluster or a tone to
indicate the condition of the system. Refer to theAirbag readiness
section in theInstrument Clusterchapter. Routine maintenance of the
side airbag is not required.
A difficulty with the system is indicated by one or more of the following:
•The readiness light (same light as for front airbag system) will either
flash or stay lit.
•The readiness light will not illuminate immediately after ignition is
turned on.
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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.
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.
Note:Some spare tires operate at a higher inflation pressure than the
other tires. For T-type/mini-spare tires (seeDissimilar Spare
Tire/Wheel Informationsection for description): Store and maintain at
60psi (4.15 bar). For Full Size and Dissimilar spare tires (seeDissimilar
Spare Tire/Wheel Informationsection for description): Store and
maintain at the higher of the front and rear inflation pressure as shown
on the Tire Label.
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 CARE
Inspecting your tires
Periodically inspect the tire treads for uneven or excessive wear and
remove objects such as stones, nails or glass that may be wedged in the
tread grooves. Check for holes or cuts that may permit air leakage from
the tire and make necessary repairs. Also inspect the tire sidewalls for
cracking, cuts, bruises and other signs of damage or excessive wear. If
internal damage to the tire is suspected, have the tire demounted and
inspected in case it needs to be repaired or replaced. For your safety,
tires that are damaged or show signs of excessive wear should not be
used because they are more likely to blow out or fail.
Improper or inadequate vehicle maintenance can cause tires to wear
abnormally. Inspect all your tires, including the spare, frequently, and
replace them if one or more of the following conditions exist:
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Owners Guide (post-2002-fmt)
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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.
Do not spin the wheels at over 35 mph (56 km/h). The tires may
fail and injure a passenger or bystander.
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.
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 cause 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 an authorized 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 an authorized dealer.
Front wheel drive (FWD) vehicles and those with an independent rear
suspension (if equipped) may 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 informationthat comes with your vehicle) will
help your tires wear more evenly, providing better tire performance and
longer tire life.
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TIRE PRESSURE MONITORING SYSTEM (TPMS)
Each tire, including the spare (if
provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label. (If your vehicle has tires
of a different size than the size indicated on the vehicle placard or tire
inflation pressure label, you should determine the proper tire inflation
pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire
pressure monitoring system (TPMS) that illuminates a low tire pressure
telltale when one or more of your tires is significantly under-inflated.
Accordingly, when the low tire pressure telltale illuminates, you should
stop and check your tires as soon as possible, and inflate them to the
proper pressure. Driving on a significantly under-inflated tire causes the
tire to overheat and can lead to tire failure. Under-inflation also reduces
fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS is not a substitute for proper tire
maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a TPMS malfunction indicator
to indicate when the system is not operating properly. The TPMS
malfunction indicator is combined with the low tire pressure telltale.
When the system detects a malfunction, the telltale will flash for
approximately one minute and then remain continuously illuminated.
This sequence will continue upon subsequent vehicle start-ups as long as
the malfunction exists.
When the malfunction indicator is illuminated, the system may not be
able to detect or signal low tire pressure as intended. TPMS malfunctions
may occur for a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle that prevent the
TPMS from functioning properly. Always check the TPMS malfunction
telltale after replacing one or more tires or wheels on your vehicle to
ensure that the replacement or alternate tires and wheels allow the
TPMS to continue to function properly.
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If you use a rental trailer, follow the instructions that the rental agency
gives to you.
Do not attach safety chains to the bumper.
Trailer brakes
Electric brakes and manual, automatic or surge-type trailer brakes are
safe if installed properly and adjusted to the manufacturer’s
specifications. The trailer brakes must meet local and Federal
regulations.
Do not connect a trailer’s hydraulic brake system directly to your
vehicle’s brake system. Your vehicle may not have enough
braking power and your chances of having a collision greatly increase.
The braking system of the tow vehicle is rated for operation at the
GVWR not GCWR.
Trailer lamps
Trailer lamps are required on most towed vehicles. Make sure all running
lights, brake lights, turn signals and hazard lights are working. See your
authorized dealer or trailer rental agency for proper instructions and
equipment for hooking up trailer lamps.
Driving while you tow
When towing a trailer:
•Keep your speed no faster than 70 mph (112 km/h) during the first
500 miles (800 km) of towing a trailer, and don’t make full throttle
starts.
•Turn off the speed control. The speed control may shut off
automatically when you are towing on long, steep grades.
•Consult your local motor vehicle speed regulations for towing a trailer.
•To eliminate excessive shifting, use a lower gear. This will also assist
in transmission cooling. (For additional information, refer to
Understanding the gearshift positions of the 4–speed automatic
transmissionin theDriving chapter.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage may occur.
Servicing after towing
If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to yourscheduled maintenance
informationfor more information.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
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Trailer towing tips
•Practice turning, stopping and backing up before starting on a trip to
get the feel of the vehicle trailer combination. When turning, make
wider turns so the trailer wheels will clear curbs and other obstacles.
•Allow more distance for stopping with a trailer attached.
•If you are driving down a long or steep hill, shift to a lower gear. Do
not apply the brakes continuously, as they may overheat and become
less effective.
•The trailer tongue weight should be 10–15% of the loaded trailer
weight.
•If you will be towing a trailer frequently in hot weather, hilly
conditions, at GCWR, or any combination of these factors, consider
refilling your rear axle with synthetic gear lube if not already so
equipped. Refer to theMaintenance and Specificationschapter for
the lubricant specification. Remember that regardless of the rear axle
lube used, do not tow a trailer for the first 500 miles (800 km) of a
new vehicle, and that the first 500 miles (800 km) of towing be done
at no faster than 70 mph (112 km/h) with no full throttle starts.
•After you have traveled 50 miles (80 km), thoroughly check your
hitch, electrical connections and trailer wheel lug nuts.
•To aid in engine/transmission cooling and A/C efficiency during hot
weather while stopped in traffic, place the gearshift lever in P (Park).
•Vehicles with trailers should not be parked on a grade. If you must
park on a grade, place wheel chocks under the trailer’s wheels.
Launching or retrieving a boat
Disconnect the wiring to the trailer before backing the trailer
into the water. Reconnect the wiring to the trailer after the
trailer is removed from the water.
When backing down a ramp during boat launching or retrieval:
•do not allow the static water level to rise above the bottom edge of
the rear bumper.
•do not allow waves to break higher than 6 inches (15 cm) above the
bottom edge of the rear bumper.
Exceeding these limits may allow water to enter vehicle components:
•causing internal damage to the components.
•affecting driveability, emissions and reliability.
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