2005 FORD F750 manual transmission

Sudden accelerations on slippery surfaces could cause the
wheels to spin, the vehicle to turn sideways on a crowned road
surface or in a turn, possibly resulting in loss of vehicle control and
personal injury.
Some Dana/Spicer drive axles have a driver-controlled differential lock.
The differential lock can lock or unlock the differential when the vehicle
is moving or stopped. When extra traction is required, the differential
lock will provide full power to both axles.
When the differential is locked, the vehicle’s turning radius will increase
(vehicle will“under-steer”)
The differential can be locked or unlocked when the vehicle is moving at
a constant speed of less than 25 mph (40 km/h) and while the wheels
are not slipping. The differential must not be locked when the vehicle is
traveling down steep grades and traction is minimal.
Note:Never use the differential lock at vehicle speeds above 25 mph (40
km/h).
Note:The driver-controlled differential lock function will vary with some
transmissions.
•Vehicle equipped with an Allison MD transmission:The
differential lock and differential lock light will automatically disengage
at speeds above 40 km/h (40 mph). The differential lock will remain
off until either the vehicle is restarted or the differential lock switch is
turned off then back on.
•Vehicle equipped with a 5–speed, 6–speed or 7–speed manual
transmissions or a non-MD automatic transmissions:The driver
must manually deactivate the differential lock if using it at speeds
above 40 km/h (25 mph).
•Vehicles equipped with a 10–speed transmission:The differential
lock can only be activated when in low range and it will only stay
activated until it is turned off or when the transmission is put into
high range. When active and shifted into high range, it will temporarily
deactivate automatically until low range is selected again.
Driving
131

Axle conversions
It is not recommended, or approved, for axle conversions to be
performed. However, it is understood that, on occasion, aftermarket
add-on axles are installed by others on the truck chassis which allow
operator control for weight transfer from other axles (i.e., air lift axles).
When operating a loaded vehicle, the driver must keep all
adjustable axles on the ground at all times, supporting their
share of the vehicle’s load. Failure to do so can overload other axles,
tires, wheels, springs, steering components, brakes and frames,
resulting in early component failure, loss of vehicle control, possible
property damage and personal injury.
TWO-SPEED REAR AXLE (IF EQUIPPED)
A two-speed rear axle allows the driver to select a LO range for greater
pulling power and a HI range for greater road speed and fuel economy.
These ranges can also be used to provide additional steps between
transmission shifts when driving on steep grades and/or fuel economy
may be factors.
Note:Do not shift between ranges when the speed control is on.
Never shift a two-speed axle when descending a steep grade as
this may cause loss of vehicle control and result in personal
injury.
Axle shifting
Manual transmissions:
•To downshift,select the next lower gear, release and depress the
accelerator pedal rapidly, or while holding the accelerator pedal down,
release and engage the clutch rapidly.Note:The clutch method is
recommended when driving at slower speeds.
•To upshift,keep the accelerator pedal down, select the next higher
gear, release the accelerator and pause until the axle upshifts.Note:
De-clutch for smoother axle upshifts when driving at slower speeds.
Driving
132

Automatic transmissions:
•Use LO range for when you drive
a fully loaded vehicle on a severe
grade or in congested traffic. To
activate LO range, press the
upper portion of the switch.
•Use HI range for all normal
driving conditions with a lightly
loaded or partially loaded vehicle.
To activate HI range, press the
lower portion of the switch.
Note:You cannot split-shift with an automatic transmission. Also,
downshifting above 40 mph (64 km/h) may result in transmission or axle
damage.
Shifting the axle from LO to HI range - vehicle stopped
Place the transmission in N (Neutral), the press the lower part of the
switch.
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.
LOW
2SPD
Driving
133

Safety chains
Always connect the trailer’s safety chains to the frame or hook retainers
of the vehicle hitch. To connect the trailer’s safety chains, cross the
chains under the trailer tongue and allow slack for turning corners.
If you use a rental trailer, follow the instructions that the rental agency
gives to you.
Do not attach safety chains to the bumper.
Trailer brakes
Electric brakes and manual, automatic or surge-type trailer brakes are
safe if installed properly and adjusted to the manufacturer’s
specifications. The trailer brakes must meet local and Federal
regulations.
Do not connect a trailer’s hydraulic brake system directly to your
vehicle’s brake system. Your vehicle may not have enough
braking power and your chances of having a collision greatly increase.
Trailer lamps
Trailer lamps are required on most towed vehicles. Your vehicle may be
equipped with one of two possible trailer wiring designs. Make sure all
running lights, brake lights, turn signals and hazard lights are working.
See your dealer or trailer rental agency for proper instructions and
equipment for hooking up trailer lamps.
Driving while you tow
When towing a trailer:
•Turn off the speed control. The speed control may shut off
automatically when you are towing on long, steep grades.
•Consult your local motor vehicle speed regulations for towing a trailer.
•To eliminate excessive transmission shifting, use a lower gear. This will
also assist in transmission cooling.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage may occur.
Servicing after towing
If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to your scheduled maintenance guide for
more information.
Driving
137

Trailer towing tips
•Practice turning, stopping and backing up before starting on a trip to
get the feel of the vehicle trailer combination. When turning, make
wider turns so the trailer wheels will clear curbs and other obstacles.
•Allow more distance for stopping with a trailer attached.
•The trailer tongue weight should be 10–15% of the loaded trailer
weight.
•After you have traveled 50 miles (80 km), thoroughly check your
hitch, electrical connections and trailer wheel lug nuts.
•To aid in engine/transmission cooling and A/C efficiency during hot
weather while stopped in traffic, place the gearshift lever in P (Park)
(if available on your automatic transmission) or N (Neutral) (manual
transmissions and automatic transmissions without a P [Park]
position).
•Vehicles with trailers should not be parked on a grade. If you must
park on a grade, place wheel chocks under the trailer’s wheels.
Driving
138

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.
Towing the vehicle with the front wheels suspended
When it is necessary to tow a vehicle with the front wheels suspended,
extra precautions must be taken to avoid transmission or differential
damage. Proceed as follows:
•Remove the axle shafts from the axle assembly to prevent the wheels
from driving the differential and the transmission.
•The wheel hub ends must be covered to prevent loss of axle lubricant
and entrance of other contaminants. If the axle shafts are not
removed, removal of the propeller shaft is required.
Note:To avoid transmission damage, vehicles should not be towed even
a short distance without suspending rear wheels or removing the axle
shaft or propeller shaft.
Note:In the event the chassis is equipped with a tandem axle and the
vehicle is to be towed from the front, the forward rear axle may be
raised to clear the road surface and secured to the frame by chains or
U-bolts, allowing only the rear rear axle to contact the road surface. Axle
shafts must be removed from the rear rear axle assembly. The wheel hub
ends must be covered 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.
Towing vehicles equipped with a driver-controlled differential lock
Note:If the vehicle must be towed to a service facility with the drive
axle wheels on the ground, it is necessary to remove the axle shafts
before the vehicle is towed.
2005 F650/750(f67)
Supplement
USA English(fus)
Roadside emergencies
151

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.
2005 F650/750(f67)
Supplement
USA English(fus)
Roadside emergencies
153

OPENING THE HOOD
The hood and fenders are held in position by a latch located on each
fender.
The parking brake must be fully set before opening the hood or
possible personal injury may occur.
If you must leave the engine running while checking under the
hood, do not allow any loose clothing, jewelry, hair or other
items to get near moving engine components or possible personal
injury may occur.
To open the hood:
1. Set the parking brake, shift into N (Neutral) (automatic transmission)
or 1 (First) (manual transmission) and turn the engine off.
2. Lift upward on the bottom of
each latch.
3. Pull the bottom of each latch
away from the fender.
2005 F650/750(f67)
Supplement
USA English(fus)
Maintenance and specifications
169