2008 Mercury Grand Marquis Owner's Manuals

Low Tire Pressure
Warning LightPossible cause Customer Action Required
Solid Warning Light Tire(s)
under-inflated1. Check your tire pressure to
ensure tires are properly
inflated; refer toInflating
your tiresin this chapter.
2. After inflating your tires to
the manufacturer’s
recommended inflation
pressure as shown on the Tire
Label (located on the edge of
driver’s door or the B-Pillar),
the vehicle must be driven for
at least two minutes over
20 mph (32 km/h) before the
light will turn OFF.
Spare tire in use Your temporary spare tire is in
use. (This includes the optional
full-sized matching wheel and
tire). Repair the damaged road
wheel/tire and reinstall it on
the vehicle to restore system
functionality. For a description
on how the system functions,
refer toWhen your temporary
spare tire is installedin this
section.
TPMS
malfunctionIf your tires are properly
inflated and your spare tire is
not in use and the light
remains ON, have the system
inspected by your authorized
dealer.
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Owners Guide (post-2002-fmt)
USA(fus)
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Low Tire Pressure
Warning LightPossible cause Customer Action Required
Flashing Warning
LightSpare tire in use Your temporary spare tire is in
use. (This includes the optional
full-sized matching wheel and
tire). Repair the damaged road
wheel and re-mount it on the
vehicle to restore system
functionality. For a description
of how the system functions
under these conditions, refer to
When your temporary spare
tire is installedin this section.
TPMS
malfunctionIf your tires are properly
inflated and your spare tire is
not in use and the TPMS
warning light still flashes, have
the system inspected by your
authorized dealer.
When inflating your tires
When putting air into your tires (such as at a gas station or in your
garage), the Tire Pressure Monitoring System may not respond
immediately to the air added to your tires.
It may take up to two minutes of driving over 20 mph (32 km/h) for the
light to turn OFF after you have filled your tires to the recommended
inflation pressure.
How temperature affects your tire pressure
The Tire Pressure Monitoring System (TPMS) monitors tire pressure in
each pneumatic tire. While driving in a normal manner, a typical
passenger tire inflation pressure may increase approximately 2 to 4 psi
(14 to 28 kPa) from a cold start situation. If the vehicle is stationary
over night with the outside temperature significantly lower than the
daytime temperature, the tire pressure may decrease approximately 3 psi
(20.7 kPa) for a drop of 30° F (16.6°C) in ambient temperature. This
lower pressure value may be detected by the TPMS as being significantly
lower than the recommended inflation pressure and activate the TPMS
warning for low tire pressure. If the low tire pressure warning light is
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
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ON, visually check each tire to verify that no tire is flat. (If one or more
tires are flat, repair as necessary.) Check air pressure in the road tires. If
any tire is under-inflated, carefully drive the vehicle to the nearest
location where air can be added to the tires. Inflate all the tires to the
recommended inflation pressure.
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. If you need to use chains, it is recommended that steel
wheels (of the same size and specifications) be used, as chains may chip
aluminum wheels.
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.
•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
VEHICLE LOADING – WITH AND WITHOUT A TRAILER
This section will guide you in the proper loading of your vehicle and/or
trailer, to keep your loaded vehicle weight within its design rating
capability, with or without a trailer. Properly loading your vehicle will
provide maximum return of vehicle design performance. Before loading
your vehicle, familiarize yourself with the following terms for determining
your vehicle’s weight ratings, with or without a trailer, from the vehicle’s
Tire Label or Safety Compliance Certification Label:
Base Curb Weight– is the weight of the vehicle including a full tank of
fuel and all standard equipment. It does not include passengers, cargo, or
optional equipment.
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Owners Guide (post-2002-fmt)
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Vehicle Curb Weight– is the weight of your new vehicle when you
picked it up from your authorized dealer plus any aftermarket
equipment.
Payload– is the combined weight of cargo and passengers that the
vehicle is carrying. The maximum payload for your vehicle can be found
on the Tire Label on the B-Pillar or the edge of the driver’s door
(vehicles exported outside the US and Canada may not have a Tire
Label). Look for“THE COMBINED WEIGHT OF OCCUPANTS AND
CARGO SHOULD NEVER EXCEED XXX kg OR XXX lb.”for
maximum payload. The payload listed on the Tire Label is the maximum
payload for the vehicle as built by the assembly plant. If any aftermarket
or authorized-dealer installed equipment has been installed on the
vehicle, the weight of the equipment must be subtracted from the
payload listed on the Tire Label in order to determine the new payload.
The appropriate loading capacity of your vehicle can be limited
either by volume capacity (how much space is available) or by
payload capacity (how much weight the vehicle should carry). Once
you have reached the maximum payload of your vehicle, do not add
more cargo, even if there is space available. Overloading or improperly
loading your vehicle can contribute to loss of vehicle control and
vehicle rollover.
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Owners Guide (post-2002-fmt)
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Example only:
Cargo Weight– includes all weight added to the Base Curb Weight,
including cargo and optional equipment. When towing, trailer tongue load
weight is also part of cargo weight.
GAW (Gross Axle Weight)– is the total weight placed on each axle
(front and rear) – including vehicle curb weight and all payload.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
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GAWR (Gross Axle Weight Rating)– is the maximum allowable
weight that can be carried by a single axle (front or rear).These
numbers are shown on the Safety Compliance Certification Label
located on the B-Pillar or the edge of the driver’s door. The total
load on each axle must never exceed its GAWR.
Note:For trailer towing information refer toTrailer towingfound in
this chapter or theRV and Trailer Towing Guideprovided by your
authorized dealer.
GVW (Gross Vehicle Weight)– is the Vehicle Curb Weight + cargo +
passengers.
GVWR (Gross Vehicle Weight
Rating)– is the maximum
allowable weight of the fully loaded
vehicle (including all options,
equipment, passengers and cargo).
The GVWR is shown on the
Safety Compliance Certification
Label located on the B-Pillar or
the edge of the driver’s door.
The GVW must never exceed the
GVWR.
Exceeding the Safety Compliance Certification Label vehicle
weight rating limits could result in substandard vehicle handling
or performance, engine, transmission and/or structural damage, serious
damage to the vehicle, loss of control and personal injury.
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GCW (Gross Combined Weight)– is the weight of the loaded vehicle
(GVW) plus the weight of the fully loaded trailer.
GCWR (Gross Combined Weight Rating)– is the maximum allowable
weight of the vehicle and the loaded trailer – including all cargo and
passengers – that the vehicle can handle without risking damage.
(Important: The towing vehicles’ braking system is rated for operation at
GVWR, not at GCWR. Separate functional brakes should be used for safe
control of towed vehicles and for trailers where the GCW of the towing
vehicle plus the trailer exceed the GVWR of the towing vehicle.The
GCW must never exceed the GCWR.
Maximum Loaded Trailer Weight– is the highest possible weight of a
fully loaded trailer the vehicle can tow. It assumes a vehicle with only
mandatory options, no cargo (internal or external), a tongue load of
10–15% (conventional trailer), and driver only (150 lb. [68 kg]).Consult
your authorized dealer (or theRV and Trailer Towing Guide
provided by your authorized dealer) for more detailed
information.
Do not exceed the GVWR or the GAWR specified on the Safety
Compliance Certification Label.
Do not use replacement tires with lower load carrying capacities
than the original tires because they may lower the vehicle’s
GVWR and GAWR limitations. Replacement tires with a higher limit
than the original tires do not increase the GVWR and GAWR
limitations.
Exceeding any vehicle weight rating limitation could result in
serious damage to the vehicle and/or personal injury.
Steps for determining the correct load limit:
1. Locate the statement “The combined weight of occupants and cargo
should never exceed XXX kg or XXX lbs.” on your vehicle’s placard.
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Owners Guide (post-2002-fmt)
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2. Determine the combined weight of the driver and passengers that will
be riding in your vehicle.
3. Subtract the combined weight of the driver and passengers from XXX
kg or XXX lbs.
4. The resulting figure equals the available amount of cargo and luggage
load capacity. For example, if the “XXX” amount equals 1,400 lbs. and
there will be five 150 lb. passengers in your vehicle, the amount of
available cargo and luggage load capacity is 650 lbs. (1400–750 (5 x 150)
= 650 lb.). In metric units (635–340 (5 x 68) = 295 kg.)
5. Determine the combined weight of luggage and cargo being loaded on
the vehicle. That weight may not safely exceed the available cargo and
luggage load capacity calculated in Step 4.
6. If your vehicle will be towing a trailer, load from your trailer will be
transferred to your vehicle. Consult this manual to determine how this
reduces the available cargo and luggage load capacity of your vehicle.
The following gives you a few examples on how to calculate the available
amount of cargo and luggage load capacity:
•Another example for your vehicle with 1400 lb. (635 kg) of cargo and
luggage capacity. You decide to go golfing. Is there enough load
capacity to carry you, 4 of your friends and all the golf bags? You and
four friends average 220 lb. (99 kg) each and the golf bags weigh
approximately 30 lb. (13.5 kg) each. The calculation would be: 1400 -
(5 x 220) - (5 x 30) = 1400 - 1100 - 150 = 150 lb. Yes, you have
enough load capacity in your vehicle to transport four friends and
your golf bags. In metric units, the calculation would be: 635 kg - (5 x
99 kg) - (5 x 13.5 kg) = 635 - 495 - 67.5 = 72.5 kg.
•A final example for your vehicle with 1400 lb. (635 kg) of cargo and
luggage capacity. You and one of your friends decide to pick up
cement from the local home improvement store to finish that patio
you have been planning for the past 2 years. Measuring the inside of
the vehicle with the rear seat folded down, you have room for 12-100
lb. (45 kg) bags of cement. Do you have enough load capacity to
transport the cement to your home? If you and your friend each weigh
220 lb. (99 kg), the calculation would be: 1400 - (2 x 220) - (12 x
100) = 1400 - 440 - 1200 = - 240 lb. No, you do not have enough
cargo capacity to carry that much weight. In metric units, the
calculation would be: 635 kg - (2 x 99 kg) - (12 x 45 kg) = 635 - 198 -
540 = -103 kg. You will need to reduce the load weight by at least
240 lb. (104 kg). If you remove 3-100 lb. (45 kg) cement bags, then
the load calculation would be:
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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