brake FORD F550 2011 Repair Manual

Hill start assist (HSA)
The hill start assist feature makes it easier to pull away when the vehicle
is on a slope without the need to use the parking brake. When the hill
start assist feature is active, the vehicle will remain stationary on the
slope for up to two seconds after you release the brake pedal. During
this time, you have time to move your foot from the brake to the
accelerator pedal and pull away. The brakes are released automatically
once the engine has developed sufficient drive to prevent the vehicle
from rolling down the slope. This is an advantage when pulling away on a
slope; for example from a car park ramp, traffic lights or when reversing
uphill into a parking space.
WARNING: The hill start assist feature does not replace the
parking brake. When you leave the vehicle, always apply the
parking brake and select first or reverse gear.
Using hill start assist
The hill start assist feature is activated automatically when the vehicle is
stopped on a slope greater than five degrees. The hill start assist feature
operates with the vehicle facing downhill if reverse gear is selected. The
hill start assist feature will not operate if the parking brake is activated.
WARNING: You must remain in the vehicle once you have
activated the hill start assist feature.
Activating hill start assist
1. Press the brake pedal to bring the vehicle to a complete standstill.
Keep the brake pedal pressed.
2. If the sensors detect that the vehicle is on a slope, the hill start assist
feature will be activated automatically.
3. When you remove your foot from the brake pedal, the vehicle will
remain on the slope without rolling away for approximately up to two
seconds. This hold time will automatically be extended if you are in the
process of driving off.
4. Drive off in the normal manner. The brakes will be released
automatically.
WARNING: If the engine is revved excessively, or if a
malfunction is detected when the hill start assist feature is
active, the hill start assist feature will be deactivated. Driving
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The RSS detects obstacles up to
6 feet (2 meters) from the rear
bumper with a decreased coverage
area at the outer corners of the
bumper, (refer to the figures for
approximate zone coverage areas).
As you move closer to the obstacle,
the rate of the tone increases. When
the obstacle is less than 10 inches
(25.0 cm) away, the tone will sound
continuously. If the RSS detects a
stationary or receding object further
than 10 inches (25.0 cm) from the
side of the vehicle, the tone will
sound for only three seconds. Once
the system detects an object
approaching, the tone will sound
again.
While receiving a warning the radio
volume may be reduced to a
predetermined level. After the
warning goes away, the radio will return to the previous volume.
The RSS may have reduced performance or an increased chance of false
detection if the tailgate is not locked and in the upright position. If the
tailgate is down, the RSS tone may be heard intermittently or
continuously. The tone may also be heard if items in the truck bed
protrude rearward outside the bed.
The RSS automatically turns on when the gearshift lever is placed in R
(Reverse) and the ignition is on. A control in the message center allows
the driver to disable the system. Refer to Message center in the
Instrument Cluster chapter for more information.
Note: If the system cannot be turned off, refer to MyKey™ restricted
features in the Locks and Security chapter for more information.
Note: If your vehicle is equipped with a fully integrated electronic trailer
brake controller (TBC) and a trailer with electric trailer brakes is
connected to your vehicle, the RSS will be disabled. When the vehicle is
shifted into reverse, the message center display will remain in the Rear
Park Aid Off selection. For more information on the TBC, refer to the
Tires, Wheels and Loading chapter.
Keep the RSS sensors (located on the rear bumper/fascia) free
from snow, ice and large accumulations of dirt (do not clean the Driving
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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 case will not
engage into 4H (4x4 High) or 2H
(2WD), perform a shift with the
transmission in N (Neutral) and the
vehicle rolling at a speed below
3 mph (5 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.
WARNING: 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 4WD system (if equipped)
2H (2WD) - For general on-road
driving. Sends power to the rear
wheels only and should be used for
street and highway driving. Provides
optimal smoothness and fuel
economy at high speeds.
4H (4X4 High) - Used for extra
traction such as in snow or icy roads or in off road situations. This
mode is not intended for use on dry pavement. 2H
4H
4L N
2H
4H
4L NDriving
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• 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.
WARNING: 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 are not 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.
WARNING: Do not spin the wheels at over 35 mph (56 km/h).
The tires may fail and injure a passenger or bystander.Driving
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Refer to Gauges in the Instrument Cluster chapter 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.
WARNING: 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 are not 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). 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. Driving
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WARNING: Always set the parking brake fully and make sure
the gearshift is latched in P (Park). Turn the ignition to the off
position and remove the key whenever you leave your vehicle.
WARNING: 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 the Driving chapter. Information on transfer case maintenance
can be found in the Maintenance and Specifications chapter. 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.
Note: If air is released from your tires, the Tire Pressure Monitoring
System (TPMS) indicator light may illuminate (if equipped).Driving
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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.
Refer to Transmission temperature gauge in the Instrument Cluster
chapter for transmission fluid temperature information.
If the front or rear axle is submerged in water, the axle lubricant should
be replaced.
After driving through mud, clean off residue stuck to rotating driveshafts
and tires. Excess mud stuck on tires and rotating driveshafts causes an
imbalance that could damage drive components.
“Tread Lightly” is an educational
program designed to increase public
awareness of land-use regulations
and responsibilities in our nations
wilderness areas. Ford Motor
Company joins the U.S. Forest Service and the Bureau of Land
Management in encouraging you to help preserve our national forest and
other public and private lands by “treading lightly.” Driving
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Driving on hilly or sloping terrain
Although natural obstacles may make it necessary to travel diagonally up
or down a hill or steep incline, you should always try to drive straight up
or straight down. Avoid driving crosswise or turning on steep
slopes or hills . A danger lies in losing traction, slipping sideways and
possibly rolling over. Whenever driving on a hill, determine beforehand
the route you will use. Do not drive over the crest of a hill without
seeing what conditions are on the other side. Do not drive in reverse
over a hill without the aid of an observer.
When climbing a steep slope or hill,
start in a lower gear rather than
downshifting to a lower gear from a
higher gear once the ascent has
started. This reduces strain on the
engine and the possibility of stalling.
If you do stall out, do not try to
turn around because you might roll
over. It is better to back down to a
safe location.
Apply just enough power to the
wheels to climb the hill. Too much
power will cause the tires to slip,
spin or lose traction, resulting in
loss of vehicle control.
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.Driving
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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 the Brakes section of
this chapter for additional information on the operation of the anti-lock
brake system.
WARNING: If you are driving in slippery conditions that require
tire cables, then it is critical that you drive cautiously. Keep
speeds down, allow for longer stopping distances and avoid aggressive
steering to reduce the chances of a loss of vehicle control which can
lead to serious injury or death. If the rear end of the vehicle slides
while cornering, steer in the direction of the slide until you regain
control of the vehicle.
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). Driving
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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.
VEHICLE USED AS A STATIONARY POWER SOURCE
Auxiliary equipment called power take-off, or PTO, is often added to the
engine or transmission to operate utility equipment. Examples include a
wheel-lift for tow trucks, cranes, tools for construction or tire service,
and pumping fluids. PTO applications draw auxiliary horsepower from
the powertrain, often while the vehicle is stationary. In this condition,
there is limited cooling air flow through the radiator and around the
vehicle that normally occurs when a vehicle is moving. The aftermarket
PTO system installer, having the most knowledge of the final application,
is responsible for determining whether additional chassis heat protection
or powertrain cooling is required, and alerting the user to the safe and
proper operation.
Ford Super Duty Vehicles are qualified for use as a stationary or mobile
power source, within limits detailed in the Ford Truck Body Builders
Layout Book, found at www.fleet.ford.com/truckbbas, and through the
Ford Truck Body Builders Advisory Service.
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.Driving
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