suspension FORD EXPEDITION 2008 3.G User Guide

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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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:
•Use only cable type chains or chains offered by Ford as an accessory
or equivalent. Other conventional link type chains may contact and
cause damage to the vehicle’s wheel house and/or body.
•Do not install chains on the front wheels. Chains on the front wheels
may interfere with suspension components.
•Chains are not recommended for use on the P275/55R20 tire.
•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.
•Do not exceed 30 mph (48 km/h) with tire chains on your vehicle.
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
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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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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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If the vehicle is above 25 mph (40 km/h), momentarily pressing the
AdvanceTrac
with RSC button will steadily illuminate the “sliding car”
icon
, however, the AdvanceTrac
with RSC system will remain
enabled until the vehicle speed drops below 25 mph. If the vehicle speed
decreases below 25 mph (40 km/h), the system will become deactivated,
but if the vehicle speed subsequently increases to above 25 mph
(40 km/h), the system will again become active. In general, the system
will be active at all times the vehicle speed is above 25 mph (40 km/h).
When in R (Reverse) or in 4L (4x4 Low), ABS and the Traction Control
feature will continue to function, however ESC and RSC are disabled.
All these conditions are normal during AdvanceTrac
with RSC
operation. Refer to the following table.
AdvanceTrac
with RSC Features
Button
functions“Sliding
car”
icon
RSC ESCEngine
Traction
ControlBrake
Traction
Control
Default at
start-upOff Enabled Enabled Enabled Enabled
Button
pressed
momentarilyIlluminated
solidDisabled
below
25 mph
(40 km/h)Disabled
below
25 mph
(40 km/h)Disabled
below
25 mph
(40 km/h)Enabled
Button
pressed and
held more
than five
secondsFlashes
then
illuminated
solidDisabled
below
25 mph
(40 km/h)Disabled
below
25 mph
(40 km/h)Disabled
below
25 mph
(40 km/h)Disabled
below
25 mph
(40 km/h)
Do not alter or modify your vehicle’s suspension or steering; the
resulting changes to the vehicle’s handling can adversely affect
the AdvanceTrac
with RSC system. Also, do not install a stereo
loudspeaker near the front center console or tunnel or under either
front seat as the vibrations can adversely affect the AdvanceTrac
with
RSC sensors located in this area.
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If the steering wanders or pulls, check for:
•Underinflated tire(s) on any wheel(s)
•Uneven vehicle loading
•High crown in center of road
•High crosswinds
•Wheels out of alignment
•Loose or worn suspension components
Variable assist steering
Your vehicle is equipped with variable assist power steering. At low
engine RPM, steering assist will adjust to reduce efforts and improve low
speed maneuverability. At high engine RPM, the assist will adjust to
improve steering feel at high speeds.
If the amount of effort required to steer your vehicle changes while
driving at a constant engine RPM, 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
•Acceleration
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 system will stay active for 40 minutes after the ignition is
turned off to accommodate any load changes. (The air compressor may
run when the vehicle is off; this is normal.)
The air suspension system can be enabled or disabled through the
message center. Refer toMessage centerin theDriver Controlschapter.
If the system is off, the rear air suspension will not operate and will not
raise (pump) or lower (vent) while the vehicle is not moving. However, if
the system determines that the vehicle is low or high and needs to make
a height adjustment while driving at speeds above 15 mph (24 km/h), the
system will pump or vent as required. Normal vehicle operation does not
require any action by the driver.
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On vehicles equipped with air suspension, turn the air
suspension and the ignition switch off prior to jacking, hoisting
or towing your vehicle.
LIMITED-SLIP AXLE (IF EQUIPPED)
This axle provides added traction on slippery surfaces, particularly when
one wheel is on a poor traction surface. Under normal conditions, the
limited slip axle functions like a standard rear axle.
Extended use of other than the manufacturer’s specified size tires on a
limited slip rear axle could result in a permanent reduction in
effectiveness. This loss of effectiveness does not affect normal driving
and should not be noticeable to the driver.
PREPARING TO DRIVE
Utility vehicles have a significantly higher rollover rate than
other types of vehicles.
In a rollover crash, an unbelted person is significantly more likely
to die than a person wearing a seat belt.
Utility vehicles and trucks have larger tires and increased ground
clearance, giving the vehicle a higher center of gravity than a passenger
car.
Vehicles with a higher center of gravity such as utility vehicles
and trucks handle differently than vehicles with a lower center
of gravity. Utility vehicles and trucks arenotdesigned for cornering at
speeds as high as passenger cars any more than low-slung sports cars
are designed to perform satisfactorily under off-road conditions. Avoid
sharp turns, excessive speed or abrupt maneuvers in these vehicles.
Failure to drive cautiously could result in an increased risk of loss of
vehicle control, vehicle rollover, personal injury and death.
Loaded vehicles, with a higher center of gravity, may handle
differently than unloaded vehicles. Do not overload your vehicle
and use extra precautions, such as driving at slower speeds, avoiding
abrupt steering changes and allowing for increased stopping distance,
when driving a heavily loaded vehicle. Over loading or loading the
vehicle improperly can deteriorate handling capability and contribute
to loss of vehicle control and vehicle rollover.
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Maintenance and Modifications
The suspension and steering systems on your vehicle have been designed
and tested to provide predictable performance whether loaded or empty
and durable load carrying capability. For this reason, Ford Motor
Company strongly recommends that you do not make modifications such
as adding or removing parts (such as lift kits or stabilizer bars) or by
using replacement parts not equivalent to the original factory equipment.
Any modifications to a vehicle that raise the center of gravity can make
it more likely the vehicle will roll over as a result of a loss of control.
Ford Motor Company recommends that caution be used with any vehicle
equipped with a high load or device (such as ladder racks or pickup box
cover).
Failure to maintain your vehicle properly may void the warranty, increase
your repair cost, reduce vehicle performance and operational capabilities
and adversely affect driver and passenger safety. Frequent inspection of
vehicle chassis components is recommended if the vehicle is subjected to
heavy off-road usage.
DRIVING THROUGH WATER
If driving through deep or standing
water is unavoidable, proceed very
slowly especially when the depth is
not known. Never drive through
water that is higher than the bottom
of the wheel rims (for cars) or the
bottom of the hubs (for trucks).
When driving through water, traction or brake capability may be limited.
Also, water may enter your engine’s air intake and severely damage your
engine or your vehicle may stall.Driving through deep water where
the transmission vent tube is submerged may allow water into the
transmission and cause internal transmission damage.
Once through the water, always dry the brakes by moving your
vehicle slowly while applying light pressure on the brake pedal.
Wet brakes do not stop the vehicle as quickly as dry brakes.
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Fuse/Relay
LocationFuse
Amp
RatingPower Distribution Box Description
36 10A* Powertrain Control Module (PCM) – Keep
alive power, Canister vent
37 15A* Transmission B+
38 30A** Third row seats (passenger side)
39 60A** Air suspension pump
40 30A** Starter motor
41 20A** IP/Console power point
42 — Not used
43 20A** 4x4 module motor
44 — Not used
45 30A** Driver seat
46 40A** Run/Start bus bar
47 30A** Air suspension – solenoids
48 — Not used
49 30A** Front wipers/washer
50 30A** PCM – bus bar
51 20A** Cargo power point
52 20A** Cigarette lighter
53 — Air suspension relay
54 — Starter relay
55 — Trailer tow connector relay (park lamp)
56 — Trailer tow connector relay (battery charge)
57 — Run/Start relay
58 — Not used
59 — PCM relay
60 — One-touch Start diode
61 — Not used
62 — Fuel pump diode
63 15A* Trailer tow connector (back-up lamp)
64 — Not used
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Fuse/Relay
LocationFuse
Amp
RatingPower Distribution Box Description
65 10A* Air suspension logic
66 — Not used
67 10A* Blower coil
68 — Not used
69 30A* Run/Start – passenger compartment fuse
panel
70 20A* PCM (sensors) – EFC, A/C clutch coil
71 5A* Fuel coil, ISP-R
72 20A* PCM (ignition coils)
73 5A* Transmission ignition
74 20A* PCM (sensors) – HEGO/CMS, MAFS, EVMV,
CMCV, Speed deactivation switch, VCT
75 5A* 4x4 Integrated Wheel Ends (IWE) solenoid
76 20A* PCM – VPWR
77 10A* ABS logic, Heated PCV
* Mini Fuses ** Cartridge Fuses
CHANGING THE TIRES
If you get a flat tire while driving, do not apply the brake heavily.
Instead, gradually decrease your speed. Hold the steering wheel firmly
and slowly move to a safe place on the side of the road.
Note:The tire pressure monitoring system (TPMS) indicator light will
illuminate when the spare tire is in use. To restore the full functionality
of the monitoring system, all road wheels equipped with tire pressure
monitoring sensors must be mounted on the vehicle.
Have a flat serviced by an authorized dealer in order to prevent damage
to the TPMS sensors, refer toTire Pressure Monitoring System
(TPMS)in theTires, Wheels and Loadingchapter. Replace the spare
tire with a road tire as soon as possible.
The use of tire sealants may damage your Tire Pressure
Monitoring System and should not be used.
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