2008 FORD SUPER DUTY 4WD

Maintain steering wheel control at all times, especially in rough terrain.
Since sudden changes in terrain can result in abrupt steering wheel
motion, make sure you grip the steering wheel from the outside. Do not
grip the spokes.
Drive cautiously to avoid vehicle damage from concealed objects such as
rocks and stumps.
You should either know the terrain or examine maps of the area before
driving. Map out your route before driving in the area. To maintain
steering and braking control of your vehicle, you must have all four
wheels on the ground and they must be rolling, not sliding or spinning.
Basic operating principles
•Do not use 4WD on dry, hard surfaced roads. Doing so will produce
excessive noise, increase tire wear and may damage drive components.
4WD modes are only intended for consistently slippery or loose
surfaces.
•Drive slower in strong crosswinds which can affect the normal steering
characteristics of your vehicle.
•Be extremely careful when driving on pavement made slippery by
loose sand, water, gravel, snow or ice.
If your vehicle goes off the edge of the pavement
•If your vehicle goes off the edge of the pavement, slow down, but
avoid severe brake application, ease the vehicle back onto the
pavement only after reducing your speed. Do not turn the steering
wheel too sharply while returning to the road surface.
•It may be safer to stay on the apron or shoulder of the road and slow
down gradually before returning to the pavement. You may lose
control if you do not slow down or if you turn the steering wheel too
sharply or abruptly.
•It often may be less risky to strike small objects, such as highway
reflectors, with minor damage to your vehicle rather than attempt a
sudden return to the pavement which could cause the vehicle to slide
sideways out of control or roll over. Remember, your safety and the
safety of others should be your primary concern.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
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Vehicles with a higher center of gravity such as utility and
four-wheel drive vehicles handle differently than vehicles with a
lower center of gravity. Utility and four-wheel drive vehicles arenot
designed 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 and 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.
•If the vehicle goes from one type of surface to another (i.e., from
concrete to gravel) there will be a change in the way the vehicle
responds to a maneuver (steering, acceleration or braking). Again,
avoid these abrupt inputs.
Parking
On some 4WD vehicles, when the transfer case is in the N (Neutral)
position, the engine and transmission are disconnected from the rest of
the driveline. Therefore, the vehicle is free to roll even if the automatic
transmission is in P (Park) or the manual transmission is in gear. Do not
leave the vehicle unattended with the transfer case in the N (Neutral)
position. Always set the parking brake fully and turn off the ignition
when leaving the vehicle.
Always set the parking brake fully and make sure the gearshift is
latched in P (Park). Turn the ignition to the LOCK position and
remove the key whenever you leave your vehicle.
If the parking brake is fully released, but the brake warning lamp
remains illuminated, the brakes may not be working properly.
See your authorized dealer.
4WD Systems
4WD (when you select a 4WD mode), uses all four wheels to power the
vehicle. This increases traction, enabling you to drive over terrain and
road conditions that a conventional two-wheel drive vehicle cannot.
Power is supplied to all four wheels through a transfer case. On 4WD
vehicles, the transfer case allows you to select 4WD when necessary.
Information on transfer case operation and shifting procedures can be
found in theDrivingchapter. Information on transfer case maintenance
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
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can be found in theMaintenance and Specificationschapter. You
should become thoroughly familiar with this information before you
operate your vehicle.
Normal characteristics
On some 4WD models, the initial shift from two-wheel drive to 4x4 while
the vehicle is moving can cause some momentary clunk and ratcheting
sounds. This is the front drivetrain coming up to speed and the
automatic locking hubs engaging and is not cause for concern.
Sand
When driving over sand, try to keep all four wheels on the most solid
area of the trail. Avoid reducing the tire pressures but shift to a lower
gear and drive steadily through the terrain. Apply the accelerator slowly
and avoid spinning the wheels.
Avoid excessive speed because vehicle momentum can work against you
and cause the vehicle to become stuck to the point that assistance may
be required from another vehicle. Remember, you may be able to back
out the way you came if you proceed with caution.
Mud and water
If you must drive through high
water, drive slowly. Traction or
brake capability may be limited.
When driving through water,
determine the depth; avoid water
higher than the bottom of the hubs
(if possible) and proceed slowly. If
the ignition system gets wet, the
vehicle may stall.
Once through water, always try the brakes. Wet brakes do not stop the
vehicle as effectively as dry brakes. Drying can be improved by moving
your vehicle slowly while applying light pressure on the brake pedal.
Be cautious of sudden changes in vehicle speed or direction when you
are driving in mud. Even 4WD vehicles can lose traction in slick mud. As
when you are driving over sand, apply the accelerator slowly and avoid
spinning your wheels. If the vehicle does slide, steer in the direction of
the slide until you regain control of the vehicle.
If the transmission, transfer case or front axle are submerged in water,
their fluids should be checked and changed, if necessary.
Driving through deep water may damage the transmission.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
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Descend a hill in the same gear you
would use to climb up the hill to
avoid excessive brake application
and brake overheating. Do not
descend in neutral; instead,
manually shift to a lower gear. Your
vehicle has anti-lock brakes, apply
the brakes steadily. Do not “pump”
the brakes.
Driving on snow and ice
4WD vehicles have advantages over 2WD vehicles in snow and ice but
can skid like any other vehicle.
Should you start to slide while driving on snowy or icy roads, turn the
steering wheel in the direction of the slide until you regain control.
Avoid sudden applications of power and quick changes of direction on
snow and ice. Apply the accelerator slowly and steadily when starting
from a full stop.
Avoid sudden braking as well. Although a 4WD vehicle may accelerate
better than a two-wheel drive vehicle in snow and ice, it won’t stop any
faster, because as in other vehicles, braking occurs at all four wheels. Do
not become overconfident as to road conditions.
Make sure you allow sufficient distance between you and other vehicles
for stopping. Drive slower than usual and consider using one of the lower
gears. In emergency stopping situations, avoid locking of the wheels. Use
a “squeeze” technique, push on the brake pedal with a steadily increasing
force which allows the wheels to brake yet continue to roll so that you
may steer in the direction you want to travel. If you lock the wheels,
release the brake pedal and repeat the squeeze technique. If your vehicle
is equipped with a Four Wheel Anti-Lock Brake System (ABS), apply the
brake steadily. Do not “pump” the brakes. Refer to theBrakessection of
this chapter for additional information on the operation of the anti-lock
brake system.
Never drive with chains on the front tires of 4WD vehicles without also
putting them on the rear tires. This could cause the rear to slide and
swing around during braking.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Driving
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•Winter weather driving capability
•Wet weather driving capability
It is not recommended that the vehicle be operated in 4WD modes with
a temporary emergency spare tire. If 4WD operation is necessary, do not
operate above speeds of 10 mph (16 km/h) or for distances above
50 miles (80 km).
3.Full-size dissimilar spare without label on wheel
When driving with the full-size dissimilar spare tire/wheel,do not:
•Exceed 70 mph (113 km/h)
•Use more than one dissimilar spare tire/wheel at a time
•Use commercial car washing equipment
•Use snow chains on the end of the vehicle with the dissimilar spare
tire/wheel
The usage of a full-size dissimilar spare tire/wheel can lead to
impairment of the following:
•Handling, stability and braking performance
•Comfort and noise
•Ground clearance and parking at curbs
•Winter weather driving capability
•Wet weather driving capability
•All-Wheel driving capability (if applicable)
•Load leveling adjustment (if applicable)
When driving with the full-size dissimilar spare tire/wheel additional
caution should be given to:
•Towing a trailer
•Driving vehicles equipped with a camper body
•Driving vehicles with a load on the cargo rack
Drive cautiously when using a full-size dissimilar spare tire/wheel and
seek service as soon as possible.
Stopping and securing the vehicle
To help prevent the vehicle from moving when you change a tire,
be sure the parking brake is set, then block (in both directions)
the wheel that is diagonally opposite to the tire being changed.
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Roadside Emergencies
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