ground clearance FORD F450 2011 Owners Manual

For 2WD vehicles and vehicles
equipped with a manual shift
4WD system:
Turn the control to ON. The
indicator light will display in the
instrument cluster.
Once the light is displayed in the instrument cluster, both rear wheel
axle shafts will be locked together providing added traction.
If the
indicator light in the instrument cluster turns off, one of the
following has occurred:
• The vehicle speed is too high.
• The left and right rear wheel speed difference is too high during an
engagement attempt.
• The system has malfunctioned and will be accompanied by the
CHECK LOCKING DIFFERENTIAL message in the message center.
See your authorized Ford dealer for assistance.
Note: The ELD may have difficulty disengaging either by operator
command or automatically if the driveline is under torque. If driving
conditions allow, releasing the accelerator pedal or turning the steering
wheel in the opposite direction may assist in disengagement.
Note: The ELD is designed for off-road use only and is not intended for
use on dry pavement.
PREPARING TO DRIVE
WARNING: Utility vehicles have a significantly higher rollover
rate than other types of vehicles.
WARNING: 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. Driving
281
2011 F-250/350/450/550 (f23)
Owners Guide, 4th Printing
USA (fus)

Note: Some noise may be heard as the system shifts or engages; this is
normal.
Note: 4x4 low mode is not intended for use on dry pavement.
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.
Your vehicle may be equipped with a long front air dam that may become
damaged (due to reduced ground clearance) when taking your vehicle
off-road. This air dam can either be removed or a shorter air dam can be
purchased from your authorized dealer. In either case, if the air dam is
to be removed (or replaced) before going off-road, refer to the
Workshop Manual for the procedure or have your authorized dealer
perform the work for you.
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.
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. Driving
303
2011 F-250/350/450/550 (f23)
Owners Guide, 4th Printing
USA (fus)

• Try to repair the dissimilar spare tire
Use of one of the dissimilar spare tires listed above at any one wheel
location 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
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 rackRoadside Emergencies
328
2011 F-250/350/450/550 (f23)
Owners Guide, 4th Printing
USA (fus)