wheel FORD EXPEDITION 2008 3.G Service Manual

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 vehicle’s 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) or king pin weight of 15–25% (fifth wheel
trailer), and driver only (150 lb. [68 kg]).Consult your authorized
dealer (or theRV and Trailer Towing Guideprovided by your
authorized dealer) for more detailed information.
Tongue Load or Fifth Wheel King Pin Weight– refers to the amount
of the weight that a trailer pushes down on a trailer hitch.
Examples:For a 5,000 lb. (2,268 kg) conventional trailer, multiply 5,000
by 0.10 and 0.15 to obtain a proper tongue load range of 500 to 750 lb.
(227 to 340 kg). For an 11,500 lb. (5,216 kg) fifth wheel trailer, multiply
by 0.15 and 0.25 to obtain a proper king pin load range of 1,725
to 2,875 lb. (782 to 1,304 kg)
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.
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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.
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
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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:
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.
Special loading instructions for owners of pickup trucks and
utility-type vehicles
For important information regarding safe operation of this type
of vehicle, see thePreparing to drive your vehiclesection in
theDrivingchapter of this owner guide.
Loaded vehicles, with a higher center of gravity, may handle
differently than unloaded vehicles. Extra precautions, such as
slower speeds and increased stopping distance, should be taken when
driving a heavily loaded vehicle.
Your vehicle has the capability to haul more cargo and people than most
passenger cars. Depending upon the type and placement of the load,
hauling cargo and people may raise the center of gravity of the vehicle.
TRAILER TOWING
Trailer towing puts additional loads on your vehicle’s engine,
transmission, axle, brakes, tires, and suspension. For your safety and to
maximize vehicle performance, be sure to use the proper equipment
while towing.
Follow these guidelines to ensure safe towing procedure:
•Stay within your vehicle’s load limits. If exceeded, cargo should be
removed from the trailer and/or the vehicle until all weights are within
specified limits.
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•Thoroughly prepare your vehicle for towing. Refer toPreparing to
towin this chapter.
•Use extra caution when driving while trailer towing. Refer toDriving
while you towin this chapter.
•Service your vehicle more frequently if you tow a trailer. Refer to the
severe duty schedule in the scheduled maintenance guide.
•Do not tow a trailer until your vehicle has been driven at least 500
miles (800 km). Additionally, during the first 500 miles (800 km) that
you tow a trailer, do not drive over 70 mph (112 km/h) and do not
make starts at full throttle.
•Refer to the instructions included with towing accessories for the
proper installation and adjustment specifications.
Trailer towing (standard equipment):
Your vehicle is equipped with a integrated trailer hitch and a Class I
(4-pin) trailer electrical connector. The 4-pin connector supplies power
to tail lamps, stop lamps, and turn lamps. See the trailer towing chart for
the trailer towing weight recommendation.
Trailer towing (optionally equipped trailer tow package):
The optional trailer tow package includes heavy duty trailer tow wiring.
Both a Class I (4-pin) and IV (7-pin) trailer electrical connector are
provided. Under the instrument panel a electrical connector is provided
for a customer supplied aftermarket electronic brake controller. For
installing a customer supplied electronic brake controller, a electrical
jumper harness and trailer tow electrical instructions are included with
the optional trailer tow package.
The kit containing a electrical jumper and trailer tow electrical
instructions may be purchased from any authorized dealer (Part number
4L1Z-14A348-AA)
Note:Before towing a trailer, make sure the trailer brakes (if equipped)
and lamps are properly connected and functional. Electronic trailer
brakes (if equipped) refer to the instructions provided by the
aftermarket electronic brake controller manufacture for determining
trailer brake functionality.
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EngineRear axle
ratioMaximum GCWR -
lb. (kg)Trailer weight
range (0 -
maximum) lb. (kg)
4x2
5.4L with
standard
trailer tow
packageAll 11800 (5351) 0–6000 (0–2721)
5.4L with
optional
trailer tow
packageAll 15000 (6803) 0–9200 (0–4172)
4x4
5.4L with
standard
trailer tow
packageAll 12100 (5488) 0–6000 (0–2721)
5.4L with
optional
trailer tow
packageAll 15000 (6803) 0–9000 (0–4082)
Note:For vehicles not equipped with the optional trailer tow package,
the maximum frontal area of trailer should not exceed the frontal area
of the vehicle (3.4 square meters [36.5 square feet]).
Note:For vehicles equipped with the optional trailer tow package, the
maximum frontal area of trailer should not exceed 5.6 square meters
(60 square feet).
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EngineRear axle
ratioMaximum GCWR -
lb. (kg)Trailer weight
range (0 -
maximum) lb. (kg)
Expedition EL (U.S. Only) Expedition Max (Canada Only) 4x2
5.4L with
standard
trailer tow
packageAll 12200 (5533) 0–6000 (0–2721)
5.4L with
optional
trailer tow
packageAll 15000 (6803) 0–8950 (0–4059)
Expedition EL (U.S. Only) Expedition Max (Canada Only) 4x4
5.4L with
standard
trailer tow
packageAll 12400 (5624) 0–6000 (0–2721)
5.4L with
optional
trailer tow
packageAll 15000 (6803) 0–8700 (0–3946 )
Note:For vehicles not equipped with the optional trailer tow package,
the maximum frontal area of trailer should not exceed the frontal area
of the vehicle (3.4 square meters [36.5 square feet]).
Note:For vehicles equipped with the optional trailer tow package, the
maximum frontal area of trailer should not exceed 5.6 square meters
(60 square feet).
Do not exceed the maximum loads listed on the Safety Compliance
Certification label. For load specification terms found on the label, refer
toVehicle loadingin this chapter. Remember to figure in the tongue
load of your loaded trailer when figuring the total weight.
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
control, vehicle rollover and personal injury.
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Integrated hitch rating
The standard integrated hitch has two ratings depending on mode of
operation:
•Weight carrying- requires a draw bar and hitch ball. The draw bar
supports all the vertical tongue load of the trailer.
•Weight distributing- requires an aftermarket weight distributing
system which includes draw bar, hitch ball, spring bars and snap-up
brackets. The vertical tongue load of the trailer is distributed between
the truck and the trailer by this system.
Mode Maximum
Gross Trailer
Weight - lb.
(kg)Maximum
Tongue Weight
- lb. (kg)
Weight carrying 6000 (2721) 600 (272)
Weight distributing 9100 (4127) 910 (412)
These are hitch ratings only; actual vehicle ratings are dependent on
engine, transmission and axle combinations.
Towing trailers beyond the maximum tongue weight exceeds the
limit of the towing system and could result in vehicle structural
damage, loss of vehicle control and personal injury.
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.
The trailer hitch on this vehicle is part of the vehicle rear crash
safety structure. Do not remove the trailer hitch. Failure to
follow this warning could compromise vehicle crash structure and
increase the risk of injury in a rear end collision.
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Weight distributing hitch
When hooking up a trailer using a load equalizing hitch, always use the
following procedure:
1. Park the unloaded vehicle on a level surface. With the ignition in the
ON position and all doors closed, allow the vehicle to stand (without
passengers) for several minutes so that it can level.
2. Turn the air suspension (if equipped) control to OFF.
3. Measure the height of a reference point on the front and rear bumpers
at the center of the vehicle.
4. Attach the trailer to the vehicle and adjust the hitch equalizers so that
the front bumper height is within a
12” (13 mm) of the reference point.
After proper adjustment, the rear bumper should be no higher than in
Step 3.
5. Turn the air suspension (if equipped) control to ON.
Note:Adjusting a weight distributing hitch so the rear bumper of the
vehicle is higher than it was unloaded will defeat the function of the
weight distributing hitch and may cause unpredictable handling.
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.
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.
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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 toDriving
with a 6-speed automatic transmissionin theDriving chapter.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage may occur.
If your vehicle is equipped with AdvanceTrac
with RSC, you may
experience AdvanceTrac
with RSC activations during typical cornering
maneuvers with a heavily loaded trailer; this is normal. Cornering at a
slower speed while towing will reduce the tendency of the AdvanceTrac

stability enhancement system to activate.
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.
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.
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•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.
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.
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