2005 FORD F750 parking brake

Releasing spring brake manually
Do not attempt to disassemble the parking brake chamber under
any circumstances. The high spring load may cause serious
injury if the chamber clamps are removed.
If air pressure is released from the spring brake chamber the power
spring applies the brake and, unless air pressure can be re-established,
the spring brake must be released as follows in order to move the
vehicle.
Block the wheels to help prevent the vehicle from moving.
Unexpected and possibly sudden vehicle movement may occur if
these precautions are not taken.
Impact wrenches should not be used as they may damage the piston and
prevent proper caging of the spring. Do not apply more than 50 lbs. ft.
(68 N•m) torque to the release bolt nut.
1. Remove the stud tool and nut
from the carrying pocket on the
brake chamber assembly.
2. Remove the access plug from the
end of the spring chamber.
3. Insert the release stud through
the opening in the chamber and into
the spring pressure plate.
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To apply the trailer brakes using the hand control, move the lever
downward. The further the lever is pushed downward, the greater the air
pressure is applied to the brakes. The lever will remain in place until
manually moved.
To release the trailer brakes, move the lever upward completely.
Trailer air supply and parking brake modular controls (if equipped)
The trailer air supply valve delivers air to the trailer supply and will
automatically pop out, shutting off the trailer supply if pressure is
decreased to approximately 35 psi (249 kPa).
The parking brake controls the spring brakes on the tractor. When the
knob is pulled out it causes the trailer supply valve to pop out, applying
both the tractor and trailer parking brakes. The trailer brakes may be
independently released by pushing only the trailer air supply valve in.
TRAILER
AIR SUPPLY
NOT FOR PARKING
TO
TOP
U
L
L
SUPPLY
EVACUATE
PUSH
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Initial charge
With the air system completely discharged, both knobs (1 and 2) will be
out. When the air pressure reaches 70 psi (483 kPa) the trailer air
supply (1–red knob) may be pushed in and should stay in charging the
trailer air system and releasing the trailer brakes.
The parking brake (2–yellow knob) can now be pushed in and supply air
to the tractor spring brakes, releasing them.
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Normal driving position
With both knobs pushed in, air is then supplied to both trailer and
tractor spring brakes, and all brakes are released.
System park
With both knobs pushed in (normal driving position), the parking brakes
for both the tractor and trailer can be applied by pulling the parking
brake knob (2) out, exhausting air from the tractor spring brakes,
simultaneously causing the trailer air supply valve to pop out, applying
the trailer brakes.
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Trailer charge
If both knobs are out, and you want to recharge the trailer while leaving
the tractor spring brakes applied, the trailer air supply (1) can be
pushed in to recharge the trailer air supply line. This mode may also be
used to park a combination vehicle with tractor spring brakes.
Automatic application
If both knobs are pushed in and the brake system air pressure is reduced
to approximately 35 psi (249 kPa), the trailer air supply (1) knob will
automatically pop out applying the emergency or parking brakes on the
trailer. If the trailer air supply (1) knob is manually held in and the air
pressure is reduced to approximately 30 psi (207 kPa), a tripper piston
within the valve will move, exhausting the trailer air supply, applying the
trailer brakes. Further reduction of air pressure, while holding the trailer
air supply knob in, will cause the parking brake knob to pop out at 25 psi
(172 kPa).
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ABS warning lamp
The
ABSwarning lamp in the instrument cluster momentarily illuminates
when the ignition is turned on and the engine is off. If the light does not
illuminate momentarily at start up, remains on after the vehicle reaches
5–10 mph (10–15 km/h), or continues to flash, the ABS needs to be
serviced.
With the ABS light on, the anti-lock brake system is disabled and normal
braking is still effective unless the brake warning light also remains
illuminated. (If your parking brake warning lamp illuminates, have your
vehicle serviced immediately).
Using ABS
•In an emergency or when maximum efficiency from the ABS is
required, apply continuous full force on the brake. The ABS will be
activated immediately, thus allowing you to retain full steering control
of your vehicle and, providing there is sufficient space, will enable you
to avoid obstacles and bring the vehicle to a controlled stop.
•The ABS does not decrease the time necessary to apply the brakes or
always reduce stopping distance. Always leave enough room between
your vehicle and the vehicle in front of you to stop.
•We recommend that you familiarize yourself with this braking
technique. However, avoid taking any unnecessary risks.
TRACTION CONTROL(IF EQUIPPED)
Your vehicle may be equipped with a Traction Controlsystem. This
system helps you maintain the stability and steerability of your vehicle,
especially on slippery road surfaces such as snow- or ice-covered roads
and gravel roads, by reducing engine power and/or selectively applying
the rear brakes. The system will allow your vehicle to make better use of
available traction in these conditions.
Note:The traction control system will not apply the brakes when the
vehicle speed is above 25 mph (40 km/h).
During Traction Controloperation,
the traction control light in the
instrument cluster will flash and the
engine will not“rev-up”when you
push further on the accelerator. This
is normal system behavior and should be no reason for concern. If the
traction control light does not flash or stays illuminated, the system is
not functioning.
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9. Charge the trailer brake system. Set the trailer brakes, either with the
hand valve or tractor protection valve. Pull against the trailer for an
additional check of proper hook-up. Do not pull hard enough to damage
or strain the equipment.
10. Set the tractor parking brakes and fully raise the trailer landing gear.
Refer toBrakesin this chapter for proper operation of the parking brake
and trailer brakes.
11. Check the operation of all trailer lights and correct any lights that
may be faulty.
Un-hook
1. Try to keep the tractor and trailer in a straight line.
2. Apply the parking brakes.
3. Lower the trailer landing gear, making sure it is on solid, level ground.
The weight of the trailer is to be on the landing gear.
4. Block the trailer wheels.
5. Disconnect the brake hoses and light cords. Be sure hoses and cords
are clear.
6. Pull coupler release lever to disengage the fifth wheel jaws.
7. Release the tractor parking brakes.
8. Pull out from the trailer slowly, allowing the landing gear to take the
load gradually.
AUTOMATIC TRANSMISSION OPERATION (IF EQUIPPED)
Main transmission, auxiliary transmission, transfer case and power
take-off (PTO) control shift patterns can be found on a placard or decal
on the driver’s sun visor, on the instrument panel or on the shift control
itself.
The main transmission control is used to select the various gear ratios or
speeds of the transmission. Selecting D (Direct Drive), does not change
the transmission gear ratio, but is used where the gear ratios in the main
transmission are adequate to handle the vehicle operation.
Hold the brake pedal down while you move the gearshift lever
between positions. If you don’t hold the brake pedal down, your
vehicle may move unexpectedly and cause property damage, personal
injury or death.
Allison 2000 automatic transmission
This transmission is available with a column-mounted gearshift lever. The
gear positions are displayed on the RNDL in the instrument cluster.
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To avoid sudden, unexpected vehicle movement and possible
personal injury or death:
1. Bring the vehicle to a complete stop.
2. Shift the transmission into: N (Neutral).
3. Apply the parking brake and make sure it is holding properly.
4. Turn the engine off when you leave the vehicle.Never leave the
vehicle unattended when the engine is running.
Allison 2400 automatic transmission with park pawl feature
Note:For Allison automatic transmission-equipped vehicles, also refer to
the separate Allison Transmission Operator’s Manual.
A parking pawl effectively grounds the transmission’s output shaft
preventing rotation of the driveline. If the vehicle is stationary, selecting
the P (Park) position places the transmission in neutral and engages the
parking pawl (always use the parking brake, also).
Note:If the P (Park) position is selected when the vehicle is in motion,
the parking pawl mechanism will ratchet andNOThold the truck.
Always set the parking brake fully. Do not use the gearshift in
place of the parking brake.
To avoid sudden, unexpected vehicle movement and possible
personal injury or death:
1. Bring the vehicle to a complete stop.
2. Shift the transmission into: P (Park). Slowly lift your foot from the
brake pedal to engage the transmission parking pawl mechanism.
3. Apply the parking brake and make sure it is holding properly. Do not
rely solely on the parking mechanism of the transmission.)
4. Turn the engine off when you leave the vehicle.Never leave the
vehicle unattended when the engine is running.
Allison MD (Medium Duty) electronic World Transmission (WT)
Two modes are available for the Allison MD-WT: Performance and
Economy. Performance mode will give you the best all-around
transmission operation; Economy provides operation at lower engine
RPM while maintaining adequate performance. The transmission will
automatically default to Performance mode when you start the engine.
Pressing MODE on the shifter will activate the Economy mode; this will
also illuminate the Mode ON lamp.
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