tow Mercury Grand Marquis 2008 s Owner's Guide

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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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:
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1400 - (2 x 220) - (9 x 100) = 1400 - 440 - 900 = 60 lb. Now you have
the load capacity to transport the cement and your friend home. In
metric units, the calculation would be: 635 kg - (2 x 99 kg) -
(9x45kg)=635-198-405=32kg.
The above calculations also assume that the loads are positioned in your
vehicle in a manner that does not overload the Front or the Rear Gross
Axle Weight Rating specified for your vehicle on the Safety Compliance
Certification Label found on the edge of the driver’s door.
TRAILER TOWING
Your vehicle is classified as a light duty towing vehicle. Do not tow a
trailer until your vehicle has been driven at least 500 miles (800 km).
Towing a trailer places an additional load on your vehicle’s engine,
transmission, brakes, tires and suspension. Inspect these components
carefully after towing.
Your loaded trailer should weigh no more than 1,500 lb. (680 kg).Do
not exceed the GVWR specified on the Safety Compliance
Certification Label.
Towing trailers beyond the maximum recommended gross trailer
weight exceeds the limit of the vehicle and could result in
engine damage, transmission damage, structural damage, loss of vehicle
control, vehicle rollover and personal injury.
The GCW of your vehicle and trailer should not exceed 6,600 lb.
(2,993 kg).
Preparing to tow
Use the proper equipment for towing a trailer and make sure it is
properly attached to your vehicle. See your authorized dealer or a
reliable trailer dealer if you require assistance.
Hitches
Do not use hitches that clamp onto the vehicle bumper. Use a load
carrying hitch. You must distribute the load in your trailer so that
10–15% of the total weight of the trailer is on the tongue.
Safety chains
Always connect the trailer’s safety chains to the frame or hook retainers
of the vehicle hitch. To connect the trailer’s safety chains, cross the
chains under the trailer tongue and allow slack for turning corners.
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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.
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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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Replace the rear axle lubricant any time the axle has been submerged in
water. Rear axle lubricant quantities are not to be checked or changed
unless a leak is suspected or repair required.
RECREATIONAL TOWING (ALL WHEELS ON THE GROUND)
Follow these guidelines for your specific powertrain combination to tow
your vehicle with all four wheels on the ground (such as behind a
recreational vehicle).
These guidelines are designed to ensure that your transmission is not
damaged due to insufficient lubrication.
All Rear Wheel Drive (RWD) vehicles:
This applies to all cars and 4x2 trucks/sport utilities with rear wheel
drive capability.
•Place the transmission in N (Neutral)
•Maximum speed is 35 mph (56 km/h)
•Maximum distance is 50 miles (80 km)
If a distance of 50 miles (80 km) or a speed of 35 mph (56 km/h) must
be exceeded, you must disconnect the driveshaft. Ford Motor Company
recommends the driveshaft be removed/installed only by a qualified
technician at an authorized dealer. See your authorized dealer for
driveshaft removal/installation.
Improper removal/installation of the driveshaft can cause
transmission fluid loss, damage to the driveshaft and internal
transmission components.
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•Be sure that areas where the vehicle is parked are clean and clear of
all combustibles such as petroleum products, dust, rags, paper and
similar items.
•Be sure that the engine block heater, heater cord and extension cord
are solidly connected. A poor connection can cause the cord to
become very hot and may result in an electrical shock or fire. Be sure
to check for heat anywhere in the electrical hookup once the system
has been operating for approximately a half hour.
•Finally, have the engine block heater system checked during your fall
tune-up to be sure it’s in good working order.
How to use the engine block heater
Ensure the receptacle terminals are clean and dry prior to use. To clean
them, use a dry cloth.
Depending on the type of factory installed equipment, your engine block
heater system may consume anywhere between 400 watts or 1000 watts
of energy per hour. Your factory installed block heater system does not
have a thermostat; however, maximum temperature is attained after
approximately 3 hours of operation. Block heater operation longer than 3
hours will not improve system performance and will unnecessarily use
additional electricity.
Make sure system is unplugged and properly stowed before driving the
vehicle. While not in use, make sure the protective cover seals the
prongs of the engine block heater cord plug.
BRAKES
Your service brakes are self-adjusting. Refer to thescheduled
maintenance informationfor scheduled maintenance.
Occasional brake noise is normal and often does not indicate a
performance concern with the vehicle’s brake system. In normal
operation, automotive brake systems may emit occasional or intermittent
squeal or groan noises when the brakes are applied. Such noises are
usually heard during the first few brake applications in the morning;
however, they may be heard at any time while braking and can be
aggravated by environmental conditions such as cold, heat, moisture,
road dust, salt or mud. If a “metal-to-metal,” “continuous grinding” or
“continuous squeal” sound is present while braking, the brake linings
may be worn-out and should be inspected by an authorized dealer.
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•loose or worn suspension components
•loose or worn steering components
•improper steering alignment
Speed sensitive steering
The steering in your vehicle is speed sensitive. At high speeds, steering
assist will decrease to improve steering feel. At lower speeds,
maneuverability will be increased.
If the amount of effort required to steer your vehicle changes while
driving at a constant vehicle speed, have the power steering system
checked by your authorized dealer.
AIR SUSPENSION SYSTEM (IF EQUIPPED)
The air suspension system is designed to improve ride, handling and
general vehicle performance during:
•Certain road conditions
•Steering maneuvers
•Braking
•Accelerations
This system keeps the rear of your vehicle at a constant level by
automatically adding air or releasing air from the springs.
If you exceed the load limit, the rear air suspension may not operate.
The air suspension shut-off switch is
located on the left side of the trunk.
If this switch is in the OFF position,
the rear air suspension will not
operate.
On vehicles equipped with
Air Suspension, turn OFF
the Air Suspension switch prior to
jacking, hoisting or towing your
vehicle.
Normal vehicle operation does not
require any action by the driver.
AIR SUSPENSION
SWITCH
INTERRUPTEUR DE
LA SUSPENSION
PNEUMATIQUE
WARNING
AVERTISSEMENTOFF-ARRET
To prevent sudden
vehicle movement,
turn off air suspen-
sion switch prior to
jacking, hoisting or
towing vehicle.
Pour prévenir tout mouvement soudain du véhi-
cule, placer à l'arrêt l'interrupteur de la suspension
pneumatique avant de lever le véhicule (cric ou
pont élévateur) ou de le remorquer.
OFF
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N (Neutral)
With the gearshift lever in N (Neutral), the vehicle can be started and is
free to roll. Hold the brake pedal down while in this position.
(Overdrive)
The normal driving position for the
best fuel economy. Transmission
operates in gears one through four.
If your vehicle is equipped with a
column-shift transmission, overdrive
can be deactivated by pressing the
transmission control switch on the
gearshift lever.
If your vehicle is equipped with a
floor-shift transmission, overdrive
can be deactivated by pressing the
transmission control switch on the
gearshift handle.
The transmission control indicator
light (TCIL) will illuminate on the
instrument cluster.
Drive (not shown)
Drive is activated when the transmission control switch is pressed.
•This position allows for all forward gears except overdrive.
•O/D OFF lamp is illuminated.
•Provides engine braking.
•Use when driving conditions cause excessive shifting from O/D to
other gears. Examples: city traffic, hilly terrain, heavy loads, trailer
towing and when engine braking is required.
•To return to O/D (overdrive mode), press the transmission control
switch. The O/D OFF lamp will not be illuminated.
O/D
OFF
O/D
OFF
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