2008 FORD SUPER DUTY Owners Manual

engaged, the vehicle speed must be below 5 mph (8 km/h) with
the brake pedal depressed and the transmission in N (Neutral). If
your vehicle is equipped with a manual transmission, the clutch
pedal also must be depressed.This vehicle is equipped with a
non-synchronous low range gearset which will not allow the
transfer case to shift into 4X4 LOW if vehicle speed is above
5 mph (8 km/h). It is recommended that a shift to 4X4 LOW is
performed while the vehicle is rolling at a speed below 5 mph
(8 km/h).
The 4WD system:
•provides 4x4 High engagement and disengagement while the vehicle is
moving.
•is operated by a rotary control located on the instrument panel that
allows you select 2WD, 4x4 High or 4x4 Low operation.
•uses auto-manual hub locks that can be engaged and disengaged
automatically based on the 4x4 mode selected.
•auto-manual hub locks can be
manually overridden by rotating
the hub lock control from AUTO
to LOCK if desired.
•automatic operation of the
hub locks is recommended,and
will increase fuel economy
•For proper operation, make
sure that each hub is fully
engaged and that both hub
locks are set to the same position (both set to LOCK or both
set to AUTO). To engage LOCK, turn the hub locks completely
clockwise; to engage AUTO, turn the hub locks completely
counterclockwise.
4WD system indicator lights
The 4WD system indicator lights illuminate only under the following
conditions. If these lights illuminate when driving in 2WD, contact your
authorized dealer as soon as possible.
•4x4 HIGH- momentarily
illuminates after the engine is
started. Illuminates when 4H (4x4
High) or 4L (4x4 Low) is
engaged.
4x4
HIGH
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•4x4 LOW– momentarily
illuminates when the ignition is
turned to the ON position.
Illuminates when 4L (4x4 Low) is
engaged.
Using a Manual Shift On Stop (MSOS) 4x4 system (if equipped)
Note: High shift efforts may be encountered when attempting to
shift into and out of 4x4 modes. It is recommended to allow the
vehicle to roll at a speed below 5 mph (8 km/h) when shifting.
Note:Some noise may be heard as the 4x4 system shifts or engages.
This is normal. In order to reduce engagement noise, it is recommended
that all shifts be performed at speeds below 5 mph (8 km/h).
2H (2WD)– For general on-road driving. Sends power to the rear
wheels only.
4H (4x4 High)– For winter and off-road conditions. Sends power to
front and rear wheels.This mode is not intended for use on dry
pavement.
N (Neutral)– Only used when towing the vehicle.
4L (4x4 Low)– For low-speed off-road applications that require extra
power such as steep grades, deep sand or pulling a boat out of the water.
Sends power to front and rear wheels.This mode is not intended for
use on dry pavement.
Shifting from 2H (2WD) to 4H (4x4 High)
Engage the locking hubs by rotating
the hub lock control from FREE to
LOCK, then move the transfer case
lever from 2H (2WD) to 4H (4x4
High) at a stop or a vehicle speed
below 5 mph (8 km/h).
•For proper operation, make
sure that both indicator
arrows on the hub are aligned,
and that both hubs are set to
LOCK.4x4
LOW
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•Do not shift into 4H (4x4
High) with the rear wheels
slipping.
Shifting from 4H (4x4 High) to 2H (2WD)
Move the transfer case lever to 2H
(2WD) at a stop or a vehicle speed
below 5 mph (8 km/h).
With the vehicle at complete stop,
disengage the locking hubs
(optional) by rotating the hub lock
control from LOCK to FREE.
•For proper operation, make
sure that both indicator arrows on the hub are aligned, and
that both hubs are set to FREE
Shifting from 4H (4x4 High) to 4L (4x4 Low)
1. Bring the vehicle to a stop or a speed below 5 mph (8 km/h).
2. Place the gearshift lever in N (Neutral). If the vehicle is equipped with
a manual transmission, also depress the clutch pedal.
3. Move the transfer case shift lever
through N (Neutral) directly to 4L
(4x4 Low).
4. If the shift lever does not, or only
partially moves to the 4L (4x4 Low)
position, perform a shift with the
transmission in N (Neutral) (or
clutch pedal depressed) and the
vehicle rolling at a speed below 5 mph (8 km/h). This will ensure the
transfer case is fully engaged into 4L (4x4 Low).
Shifting from 4L (4x4 Low) to 4H (4x4 High) or 2H (2WD)
1. Bring the vehicle to a stop or a speed below 5 mph (8 km/h).
2. Place the gearshift lever in N (Neutral). If the vehicle is equipped with
a manual transmission, also depress the clutch pedal.2H
4H
4LN
2H
4H
4LN
2H
4H
4LN
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3. Move the transfer case shift lever
through N (Neutral) directly to 4H
(4x4 High) or 2H (2WD).
4. If the transfer casewill not
engage into 4H (4x4 High) or 2H
(2WD), perform a shift with the
transmission in N (Neutral) (or
clutch pedal depressed) and the
vehicle rolling at a speed below 5 mph (8 km/h).
5. If shifting to 2H (2WD) with the vehicle at a complete stop, disengage
the locking hubs (optional) by rotating the hub lock control from LOCK
to FREE.
Using the N (Neutral) position
The transfer case neutral position overrides the transmission and
puts the vehicle in neutral regardless of transmission gearshift
lever position. The vehicle can move forward or backwards.
This position should only be used
when towing the vehicle.
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.
Using the Electronic Shift On the Fly (ESOF) 4x4 system
(if equipped)
Positions of the electronic shift system
Note:Some noise may be heard as the 4WD system shifts or engages.
This is normal.
2WD– For general on-road driving. Sends power to the rear wheels only.
4x4 HIGH– For winter and off-road conditions. Sends power to front
and rear wheels.This mode is not intended for use on dry
pavement.
2H
4H
4LN
2H
4H
4LN
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4x4 LOW– For low-speed off-road applications that require extra power
such as steep grades, deep sand or pulling a boat out of the water. Sends
power to front and rear wheels.This mode is not intended for use on
dry pavement.
Shifting from 2WD to 4x4 HIGH
Rotate the 4x4 control to the 4x4
HIGH position at speeds up to
55 mph (88 km/h).
•The electronic shift 4x4
system is designed to engage
4x4 HIGH when the vehicle is
moving. If shifted to 4x4
HIGH while at complete stop,
4x4 may not engage and the
4x4 indicator may not
illuminate until the vehicle is
allowed to move at a speed above 1 mph (1.6 km/h).
•Do not shift into 4x4 HIGH with the rear wheels slipping.
Shifting from 4x4 HIGH to 2WD
Rotate the 4x4 control to 2WD at
any forward speed. Disengagement
of the transfer case and front hubs
may be delayed due to torque bind
which is caused by driving on dry
hard surfaces or performing tight
turns while using the 4x4 system.
•Yo udo notneed to operate the vehicle in R (Reverse) to disengage
your front hubs, but it will eliminate any torque bind and allow the
system to immediately disengage.
Shifting from 4x4 HIGH to 4x4 LOW
1. Bring the vehicle to a complete stop.
2. Depress the brake.
3. Place the gearshift in N (Neutral). If the vehicle is equipped with a
manual transmission, also depress the clutch pedal.
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4. Move the 4x4 control to the 4x4
LOW position.
5. Hold the shift conditions until the
4x4 LOW indicator light illuminates.
6. If the 4x4 LOW indicator light
does notilluminate within 15
seconds, allow the vehicle to move
at a speed below 5 mph (8 km/h),
then repeat steps 2 through 5 while
the vehicle is rolling before
reporting any shift concerns to your authorized dealer.
Shifting from 4x4 LOW to 4x4 HIGH or 2WD
1. Bring the vehicle to a complete stop.
2. Depress the brake.
3. Place the gearshift in N (Neutral).
4. Move the 4x4 control to the 4x4
HIGH or 2WD position.
5. Hold the shift conditions until the
4x4 LOW indicator light shuts off.
6. If the 4x4 LOW indicator light
does notshut off within 15
seconds, allow the vehicle to move
at a speed below 5 mph (8 km/h),
then repeat steps 2 through 5 while
the vehicle is rolling before
reporting any shift concerns to your authorized dealer.
Driving off-road with truck and utility vehicles
4WD vehicles are specially equipped for driving on sand, snow, mud and
rough terrain and have operating characteristics that are somewhat
different from conventional vehicles, both on and off the road.
How your vehicle differs from other vehicles
Truck and utility vehicles can differ from some other vehicles. Your
vehicle may be higher to allow it to travel over rough terrain without
getting hung up or damaging underbody components.
The differences that make your vehicle so versatile also make it handle
differently than an ordinary passenger car.
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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.
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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 your vehicle gets stuck
If your vehicle gets stuck in mud or snow it may be rocked out by
shifting between forward and reverse gears, stopping between shifts, in a
steady pattern. Press lightly on the accelerator in each gear.
Do not rock the vehicle if the engine is not at normal operating
temperature or damage to the transmission may occur.
Do not rock the vehicle for more than a few minutes or damage
to the transmission and tires may occur or the engine may
overheat.
Do not spin the wheels at over 35 mph (56 km/h). The tires may
fail and injure a passenger or bystander.
Refer toTransmission fluid temperature gaugein theInstrument
Clusterchapter for transmission fluid temperature information.
Emergency maneuvers
•In an unavoidable emergency situation where a sudden sharp turn
must be made, remember to avoid “over-driving” your vehicle, i.e.,
turn the steering wheel only as rapidly and as far as required to avoid
the emergency. Excessive steering will result in less vehicle control,
not more. Additionally, smooth variations of the accelerator and/or
brake pedal pressure should be utilized if changes in vehicle speed are
called for. Avoid abrupt steering, acceleration or braking which could
result in an increased risk of loss of vehicle control, vehicle rollover
and/or personal injury. Use all available road surface to return the
vehicle to a safe direction of travel.
•In the event of an emergency stop, avoid skidding the tires and do not
attempt any sharp steering wheel movements.
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