2015 FORD F750 lock

Releasing Spring Manually
WARNING:Do not attempt to disassemble the parking brake
chamber under any circumstances. The high spring load may
cause serious injury.
WARNING:Block the wheels to help prevent the vehicle from
moving.
WARNING:Unexpected and possibly sudden vehicle movement
may occur if these precautions are not taken.
If you release hydraulic pressure from the spring brake chamber the
power spring applies the brake and, unless hydraulic pressure can be
re-established, you must release the spring brake as follows in order to
move your vehicle.
Loosen the jam nut (A) and un-thread the adjustment rod (B) from the
chamber to reduce tension on the cable (C). Continue to un-thread the
adjustment rod all the way and remove it from the chamber. The nut and
shaft are metric.
CA
B
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

the system with air from an outside source, releasing the spring-actuated
parking brakes. Your vehicle is now ready to tow in an emergency.
You can only use an outside air source if the protected system is in
operating condition. If you cannot restore air pressure in the protected
air system, you must release the spring-actuated brakes manually.
Releasing Spring Manually
WARNING: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 you release air pressure from the spring brake chamber, the power
spring applies the brake and, unless air pressure can be re-established,
you must release the spring brake as follows in order to move your
vehicle.
WARNING:Block the wheels to help prevent the vehicle from
moving.
WARNING:Unexpected and possibly sudden vehicle movement
may occur if these precautions are not taken.
Do not use impact wrenches as they may damage the piston and prevent
proper caging of the spring. Do not apply more than 50 foot-pounds
(68 newton-meters) 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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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

If you install an electrical back up alarm, connect it to the backup lamp
circuit.
Parking
WARNING:When parking your vehicle, do not leave the
transmission in gear; if the key is in the on position and the
vehicle rolls, the engine could start. Failure to follow these instructions
could result in an unattended vehicle moving, possibly causing personal
injury or property damage.
Always use the parking brake. When parking on a grade, block the
wheels and turn the front wheels to one side so that if your vehicle rolls,
the front tires act against the curb to stop your vehicle. The front wheels
are more effective at stopping a rolling vehicle than the rear wheels.
Cold Weather
Note:Idling in cold weather does not heat the engine to its normal
operating temperature. Long periods of idling in cold weather can cause
a build-up of heavy deposits of carbon and rust on valve stems causing
them to stick which, in turn, can cause valvetrain damage.
Note:We recommend against using winter fronts, or other air-restrictive
devices mounted in front of the radiator on vehicles with
chassis-mounted charge air coolers, unless extremely cold weather
conditions exist. Airflow restriction can cause high exhaust temperatures,
power loss, excessive fan usage and a reduction in fuel economy. If you
must use a winter front, the device should have a permanent opening of
at least 120 square inches (774 square centimeters) directly in line with
the fan hub.
For best engine operation in temperatures of 32°F (0°C) or lower:
•Make sure the batteries are the correct type and are fully charged.
Check other electrical components to make sure they are in optimum
condition.
•Use a permanent-type engine coolant to protect the engine against
damage from freezing.
•If your vehicle is equipped with a water-fuel separator, drain it daily.
Fill the fuel tank at the end of daily operation to prevent
condensation in the fuel system.
•Use the proper engine oil and maintain it at its proper level.
160Driving Aids
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Unloaded or Lightly Loaded Vehicles
WARNING:When operating empty or lightly loaded, sudden or
hard braking may induce wheel lockup with loss of vehicle
control and the possibility of accident and serious injury, especially on
wet or slippery road surfaces.
The braking system has been designed to safely stop your vehicle when
fully loaded to its GVWR.
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

•Place the gearshift lever in positionP(if equipped) or neutral to aid
in engine and transmission cooling and air conditioning efficiency
during hot weather while stopped in traffic.
•Turn off the speed control. The speed control may turn off
automatically when you are towing on long, steep grades.
•Shift to a lower gear when driving down a long or steep hill. Do not
apply the brakes continuously, as they may overheat and become less
effective.
•Allow more distance for stopping with a trailer attached. Anticipate
stops and brake gradually.
FIFTH WHEEL OPERATION
WARNING:Failure to follow the fifth wheel manufacturer’s
instructions for hooking and unhooking as well as sliding the fifth
wheel could result in an accident, personal injury or death.
WARNING:When the tractor and trailer are parked unattended,
the trailer brake hand control should never be used to apply the
brake, since air may leak from the system, allowing vehicle movement,
resulting in possible property damage, personal injury or death.
Before hook-up, make sure:
•The fifth wheel jaws are fully open.
•The fifth wheel is fully tilted back to prevent body damage when the
tractor is backed under a trailer.
•You block the trailer wheels and adjust and apply the trailer spring
brakes. Never chase a trailer.
•The brake hoses and light cords are clear of the fifth wheel.
Hook-up
1. Back the tractor squarely under the trailer, engaging the fifth-wheel
jaws on the kingpin. Always back up slowly; make sure the trailer is
neither too high nor too low. Avoid backing under the trailer from an
angle.
2. Connect the service and emergency brake hoses and trailer light
connector.
3. Inspect the jaws of the fifth wheel to be sure they have fully closed
on the trailer kingpin and the trailer plate is resting securely on the
fifth wheel.
170Towing
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

4. Make sure the coupler release lever is in the locked position.
5. Charge the trailer brake system. Set the trailer brakes, with either
the hand valve or tractor protection valve. Pull against the trailer for
an extra check of proper hook-up. Do not pull hard enough to
damage or strain the equipment.
6. Set the tractor parking brakes and fully raise the trailer landing gear.
See theBrakeschapter for proper operation of the parking brake
and trailer brakes.
7. 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.
WRECKER TOWING
WARNING:To reduce the risk of personal injury or property
damage when manually releasing the spring brakes, be sure to
block the wheels so the vehicle cannot move once the brakes are
released.
Note:Make sure to connect your vehicle securely to the tow vehicle and
that the tow vehicle’s parking brakes are set before releasing the disabled
vehicle’s spring brakes.
Before moving the disabled vehicle, check for adequate road clearance of
vehicle components. If possible, unload the disabled vehicle before
towing. This reduces any abnormal load to the vehicle components
resulting from the towing procedures. Before towing, make sure to
release the parking brake fully. You can reset the spring-actuated type
parking brake by recharging the air system with at least 64 psi (441 kPa)
of air. If the brake system does not retain air pressure, then you must
release the spring brakes manually. SeeParking brakein theBrakes
chapter.
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Towing the Vehicle with the Front Wheels Suspended
Note:To avoid transmission damage, do not tow your vehicle even a
short distance without suspending rear wheels or removing the axle
shafts or driveshaft.
Note:When towing a vehicle equipped with a tandem axle from the
front, raise the forward rear axle so it can clear the road surface and
secure it to the frame with chains or U-bolts, allowing only the rear rear
axle to contact the road surface. Remove axle shafts from the rear rear
axle assembly. Cover the wheel hub ends to prevent loss of axle lubricant
and entrance of contaminants. Use extreme care in securing the chains
or U-bolts to avoid possible damage to the brake lines, hoses or other
components.
When it is necessary to tow a vehicle with the front wheels suspended,
take extra precautions to avoid transmission or differential damage:
•Remove the axle shafts from the axle assembly to prevent the wheels
from driving the differential and the transmission.
•Cover the wheel hub ends to prevent loss of axle lubricant and
entrance of other contaminants. If you do not remove the axle shafts,
removal of the driveshaft is required.
Towing the Vehicle with the Rear Wheels Suspended
Note:To avoid damage to the cab roof or air deflector when towing your
vehicle backward (rear wheels suspended), remove the air deflector.
Whenever possible, it is preferable to tow a disabled vehicle from the
rear by raising the rear of the chassis. When towing a vehicle with the
rear of the chassis suspended, you must lock the front wheels in the
straight-ahead position.
Vehicles equipped with a manual transmission must have at least 1.0 pint
(0.5 liter) of transmission fluid drained from the case. This prevents the
transmission fluid from entering the clutch housing and saturating the
clutch discs. Make sure to replace the transmission fluid before returning
your vehicle to service.
Towing Vehicles Equipped with a Driver-controlled Differential
Lock
Note:If you have to tow your vehicle to a service facility with the drive
axle wheels on the ground, it is necessary to remove the axle shafts
before towing your vehicle.
172Towing
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

A. Side gear
B. Differential (plain) case half
C. Shift collar in the locked position
D. Actuator assembly and shift fork
E. Axle shaft
F. Interference between the shift
collar and housing
G. Shift collar in the unlocked
position
H. Outer splines: axle shaft to collar
I. Shift collar and differential case
splines
J. Inner splines: axle shaft to side
gear
Removing Axle Shafts before Towing
1. Shift the main differential to the unlocked (disengaged) position; the
differential lock light turns off.
2. Remove the cap screws and washers or stud nuts and washers from
flanges of both axle shafts.
3. Loosen the tapered dowels in the flanges of both axle shafts by
holding a 1
12inch diameter brass drift or hammer against the axle
shaft center and hitting it with a five or six pound hammer.Note:Do
not use a chisel or wedge to loosen the axle shafts and dowels. Use
of a chisel or wedge can damage the hub, axle shafts and oil seals.
4. Remove the tapered dowels and both axle shafts from the axle
assembly.
5. Assemble a cover over openings of both wheel ends to prevent loss of
lubricant and keep dirt away from the wheel bearing cavities.
Note:One of the axle shafts has two sets of splines. One set to engage
with the differential side gear and one set to engage with the shift collar
for the differential lock. It may be necessary to rotate the shaft slightly
to align the gear spline teeth with the shift collar teeth in order to
remove the axle shaft.
E
D
CB
A
J
IH
G
F
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2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)