2004 FORD F650 torque

Releasing spring brake with air pressure
The air system in all vehicles with spring-actuated rear wheel parking
brakes is equipped with a tank valve located on the supply or service air
tank for connection to an outside air supply. The valve permits the
system to be recharged with air from an outside source, releasing the
spring-actuated parking brakes. The vehicle may then be towed in an
emergency.
An outside air source can be used only if the protected system is in
operating condition. If air pressure cannot be restored in the protected
air system, the spring-actuated brakes must be released manually.
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 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 68 Nm (50
lb-ft) 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.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
102

If the engine speed is above idle when a gear is selected using the
shifter, the vehicle will not move. To move the vehicle, the shifter must
be moved to re-select a gear after the engine speed returns to idle.
Note:For more information regarding the Allison MD-WT, refer to the
separate Allison MD-WT Operator’s Manual.
Torque lock
If your vehicle is parked on an incline and P (Park) is not properly
engaged (The parking brake is not applied before the transmission is
shifted into P [Park]), the weight of the vehicle may generate an
excessive amount of torque on the park pawl. In this situation, it may be
difficult to shift the transmission out of P (Park). Hold the brake pedal
down while shifting out of P (Park), then release the parking brake.
Allison MD (Medium Duty) push-button shifter
To shift the transmission into R
(Reverse) or D (Drive), depress the
brake pedal, then press R or D, then
release the brake pedal. To select a
lower range when in D (Drive),
press the down-arrow button. To
select a higher range when in D
(Drive), press the up-arrow button.
To place the transmission in N
(Neutral), press N.
Automatic transmission operating temperatures
Allison 2000/2400–The sump/fluid reservoir temperatures should not
exceed 120°C (250°F). The converter temperature should not exceed
144°C (300°F).
Power take-off (PTO) operation with an Allison automatic
transmission (except MD applications and vehicles equipped with
a Caterpillar 3126E engine)
The power take-off can be operated while the vehicle is standing or
moving.
To engage the PTO, apply the brakes and shift to any gear other than N
(Neutral) - this stops the rotation of the PTO drive gear in the
transmission - then engage the PTO.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
117

Power take-off (PTO) operation with an Allison automatic
transmission (MD applications)
The PTO drive gear is engine driven and provides direct engine power.
The PTO can be operated when the vehicle is either stationary or
moving.
The PTO gear is in constant mesh with the drive gear in the torque
converter housing. A friction clutch or constant drive is used to transmit
power to the PTO.
CLUTCH (IF EQUIPPED)
Properly maintain the clutch to prolong it’s life. Do not ride or slip the
clutch as this will cause unnecessary heat and wear.
Clutch precautions
Maintain specified clutch adjustment; regularly inspect the clutch control
linkage for tightness.
When adjustment of the clutch is necessary, it is very important that the
work be performed properly or early clutch failure may result and a
costly clutch overhaul may become necessary. Clutch work should only
be performed by a qualified technician.
Engaging the clutch
•Always start in the proper gear.An empty vehicle can start in a
higher gear than a fully loaded vehicle. Starting in too high a gear can
cause clutch slippage and excessive heat and wear on the clutch. A
gear that will start the vehicle moving at idle speed is the correct gear.
If the engine has to be revved to get the vehicle going, the gear
selection is too high.
•Do not shift until the vehicle has reached the proper speed.
Upshifting before the vehicle has reached the proper speed can cause
clutch slippage and excessive heat and wear on the clutch.
•Never hold a vehicle on a grade with the clutch.This will cause
the clutch to slip and can actually burn up the clutch.
•Never coast with the clutch disengaged.The high RPM
(sometimes over 10,000), can actually burst the facing material of the
clutch.
•Never engage the clutch while coasting.Re-engaging the clutch
after coasting may not only cause a great shock to the clutch, but the
whole drivetrain. Internal engine damage and/or clutch and flywheel
failure can result from this.
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
119

To start forward, place the gearshift lever in LO gear and disengage the
clutch while slightly depressing the accelerator. Operate the clutch and
upshift through the shift pattern (up to 4th) as required by driving
conditions. To shift into the HI range from 4th gear (LO range), place
the range control button in the HI range, then shift to 5th gear. Upshift
through 8th. When downshifting, shift 8-7-6-5, depress the range control
button to LO, then move the gearshift lever to 4-3-2-1-LO as necessary.
Never move the gearshift lever to the LO position when the transmission
is in the HI range.
Use LO-LO only for adverse conditions by changing the Deep Reduction
Button to the IN/FORWARD position, while the range selector is in the
LO range and the gearshift lever is in the LO position. Do not pre-select
Deep Reduction.
To upshift from LO-LO to LO in the
same gearshift lever position, move
the Deep Reduction Button to the
OUT/REARWARD position and
immediately release the accelerator,
depress the clutch pedal once to
break torque, and re-engage clutch.
The transmission will shift from Deep Reduction to low range when
synchronous is reached, then accelerate.
To go backward
Reverse is obtained by putting the
gearshift lever in R (Reverse) and
the range control button in LO or HI
(Deep Reduction Button should be
in the OUT/REARWARD position).
27
3
6
2 LO
LO-LO
8
4
R R
R R
5 1
1
Neutral
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
125

Shifting the axle from LO to HI range - vehicle moving
Accelerate to approximately 56 km/h (35 mph), press the lower part of
the switch while the transmission is in N (Neutral), then release and
apply the accelerator.
Shifting the axle from HI to LO range - vehicle stopped
Place the transmission in N (Neutral), then press the upper part of the
switch.
Note:Do not shift the axle to LO range with the vehicle in motion.
Split-shifting (combined axle and transmission shift - manual
transmissions only)
Split-shift sequence
Ratio
combination1234567891011
Transmission
gear1st 1st 2nd 2nd 3rd 3rd 4th 4th 5th 6th 6th
Axle range LO HI LO HI LO HI LO HI LO LO HI
To downshiftthe axle to a slower ratio and shift the transmission, shift
the transmission and move the control switch to the lower ratio before
the clutch is re-engaged.
To upshiftthe axle and shift the transmission, move the control switch
to a faster ratio and make the transmission shift in the usual manner.
Ratio extender use
Low End
A two-speed axle can be used as a ratio-extender when split shifting is
not necessary. For low end use, just shift the axle into the LO to start
out, and shift to HI when the extra torque is no longer needed.
Transmission
(5-speed)1st 1st 2nd 3rd 4th 5th 6th
Two-speed Axle Axle
LowAxle High
2004 F650/750(f67)
Supplement
USA English(fus)
Driving
130

Installing the axle shafts
1. Remove the covers from the wheel ends
2. Shift the differential lock to the unlocked position (disengaged)
position.
3. Install the axle shafts
•Place the gaskets on the wheel hub studs.
•Push the right-hand axle shaft and gasket in to the wheel end and
housing until the shaft stops against the differential shift collar.
•Push down and in on the axle shaft flange and rotate the shaft until
the splines of the shaft and shift collar are engaged.
•Push the axle shaft further into the housing until the shaft stops
against the differential side gear.
•Push down on the axle shaft flange and rotate the shaft until the
splines of the shaft and side gear are engaged.
•Push the axle shaft completely into the housing until the axle shaft
flange and the gasket are flush against the wheel hub.
•Install the left-hand axle shaft and gasket into the wheel end.
4. If tapered dowels are required, install them at each stud and into the
flange of the axle shaft. Use a punch or drift and hammer, if needed.
5. Install the fasteners and tighten to correct torque value. Refer to the
Service Manual section.
Towing the vehicle with the rear wheels suspended
Note:To avoid damage to the cab roof or air deflector when towing the
vehicle backward (rear wheels suspended) the air deflector must be
removed.
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 the front wheels must be locked in the
straight-ahead position.
Vehicles equipped with a manual-shift transmission must have at least
one (1) pint of transmission fluid drained from the case. This will
prevent the transmission fluid from entering the clutch housing and fluid
saturating the clutch discs. Make sure that the transmission fluid is
replaced before the vehicle is returned to service.
2004 F650/750(f67)
Supplement
USA English(fus)
Roadside emergencies
149

Check to make sure that the axle mounting U-bolt nuts, attaching or
mounting bolts and nuts are securely tightened. Regularly check front
axle for damage, binding, worn parts and adequate lubrication.
At regular intervals, or during other scheduled maintenance, (tire
rotation/service, wheel bearing service, alignment, etc.) the kingpins
should be checked for excessive wear. Refer to the service manual for
proper procedures.
Toe-in setting - general inspection
Inspecting steer axle tires in the first 4,800–16,000 service km
(3,000–10,000 service miles) will generally show if tires are wearing
normally.
Rapid outside shoulder wear on both tires indicates too much toe-in.
Rapid inside shoulder wear on both tires indicates too much toe-out. In
P&D-type service, which includes school buses, left-to-right steer tire
tread life differentials up to 40% can be observed depending on routes
and other variables.
Follow the tire manufacturer’s recommended cold inflation pressure for
the tire size, load range (ply rating) and steer axle loading typical for
their operation (each steer axle tire will equal
1⁄2steer axle loading).
Special applications may warrant a setting based on past experience with
the type of tire operating loads and conditions. Radial tires are more
sensitive to toe-in setting than bias ply tires. While not insensitive to
vehicle alignment, fine tuning school bus alignment to line-haul truck
standards will not drastically improve tire tread life.
It is essential that correct toe-in and tire pressure be maintained for
optimum tire wear.
Rear axle - general inspection
Check to make sure that the axle mounting U-bolts, attaching or
mounting bolts and nuts are securely tightened. Refer toU-bolt nut
torque chartin this chapter. Regularly check the rear axle for damaged,
binding or worn parts.
NoSpin Detroit Locker positive locking differential
Vehicle equipped with this type differential have the operator’s manual
supplied with the vehicle. Refer to this manual for maintenance checks.
Brake system - general inspection
Your vehicle is equipped with non-asbestos brake linings. However,
exposure to excessive amounts of brake material (whether asbestos or
2004 F650/750(f67)
Supplement
USA English(fus)
Maintenance and specifications
160

•Check that torque rod mounting fasteners are tight.
•Check to be sure the suspension alignment is maintained at all time.
•Check U-bolts after the chassis has been operating under load for
1,600 km (1,000 miles) or six months, whichever comes first, the
U-Bolt nuts must be re-torqued. The U-Bolt nuts thereafter must be
re-torqued every 58,000 km (36,000 miles). The U-Bolt and nut
threads and seats should be cleaned and lubricated to assure a“like
new”condition when re-torquing.
Note:See theU-Bolt Nut Torquechart later in this section.
Supporting your vehicle for service
When performing service repairs on your vehicle, first prepare the
vehicle by doing the following:
1. Park the vehicle on a level concrete floor.
2. Set the parking brake and block the wheels to prevent the vehicle
from moving.
3. Select a jack (floor jack preferred) with a rated capacity sufficient to
lift and hold up the vehicle.
4. Raise the vehicle with the jack applied to the axle(s). DO NOT use the
bumper as a lifting point.
5. Support the vehicle with floor stands under the axle(s). If the axle or
the suspension are being serviced, support the vehicle with floor stands
under the frame side-members, preferably between the axles.
Do not use a jack when working under a vehicle. It may give
way, causing the vehicle to fall and result in property damage,
personal injury or death. Always use floor stands to support the
vehicle.
FRAME AND TOW HOOKS
Your vehicles chassis is manufactured with frame rails of either mild
carbon steel, or HSLA steel. Each must be handled in a specific manner
to assure maximum service life. Before attempting frame repair or
modification, consult the service manual or your dealer.
It is important, particularly on vehicles where the tow hooks are used
frequently to inspect the front and rear tow hooks for damage or a loose
mounting.
2004 F650/750(f67)
Supplement
USA English(fus)
Maintenance and specifications
196