2015 FORD F750 differential

Diesel Exhaust Fluid (diesel engine only)
It illuminates when the diesel exhaust fluid level falls below
0.5 gallons (1.9L) in the 5- gallon (19.0L) tank or one gallon
(3.8L) in the 9-gallon (34.0L) tank. Refill the tank or, at a
minimum, add at least one gallon (3.8L) to the 5- gallon (19.0L) tank or
two gallons (7.6L) to the 9- gallon (34.0L) tank.
Diesel Particulate Filter (diesel engine only)
It illuminates when the soot level in the diesel particulate filter
has reached a point where it requires operator assistance. See
Diesel particulate filterin theMaintenancechapter, and your
engine operator’s manual, for more details.
Do Not Shift (Allison automatic transmission only)
It illuminates while driving if a transmission problem exists;
shifting may be restricted. Depending on the severity of the
problem, the shifter’s digital read-out may turn blank.
Operation may continue in order to reach service assistance. The control
unit may not respond to shift selector requests, since there are operating
limitations on the transmission (such as. upshift and downshift
restrictions). Direction changes do not occur.
Direction Indicator
It illuminates when you turn on the left or right turn signal or
the hazard warning flasher. If the indicators stay on or flash
faster, check for a burned out bulb.
Electronic Locking Differential
It illuminates when using the electronic locking differential.
Engine Oil Pressure (gasoline engine only)
It illuminates when engine oil pressure is low.
Fasten Safety belt
It illuminates and a tone sounds to remind you to fasten your
safety belt.
Instrument Cluster69
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

To engage the PTO unit, stop your vehicle, place the transmission in
positionN.Press the clutch, and allow the gears to stop rotating, and
then engage the PTO unit. You can also select the PTO with the
transmission in gear as long as the clutch is pressed.
When operating the PTO with your vehicle stationary, first set the
parking brake (chock the wheels if your vehicle is on a hill or another
uneven surface).
REAR AXLES
Gross Axle Weight
WARNING:Exceeding these ratings by overloading can cause
component failure resulting in property damage, personal injury
or death.
Your truck has gross axle weight, gross vehicle weight and gross
combination weight ratings. Do not exceed these ratings.
Locking or Limited-Slip Differentials
WARNING:If both wheels are not raised off the ground, the one
wheel that is not raised may pull the vehicle off its support,
possibly resulting in personal injury
If your vehicle is equipped with a locking or limited-slip differential, note
the following:
•Power is transmitted to the opposite wheel should one of the wheels
begin to slip.
•Both wheels must be raised off the ground should it be necessary to
operate one wheel with your vehicle stationary.
Driver-controlled Differential Lock
Note:Never use the differential lock at vehicle speeds above 25 mph
(40 km/h).
Some drive axles have a driver-controlled differential lock. The
differential lock can lock or unlock the differential when your vehicle is
moving or stopped. When extra traction is required, the differential lock
provides full power to both axles.
When you lock the differential, your vehicle’s turning radius increases
(under-steer).
134Transmission
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

You can lock and unlock the differential when your vehicle is moving at a
constant speed of less than 25 mph (40 km/h) and while the wheels are
not slipping. Do not lock the differential when your vehicle is traveling
down steep grades and traction is minimal.
The differential lock and differential lock light automatically disengage at
speeds above 25 mph (40 km/h). The differential lock remains off until
either you restart your vehicle or you turn the differential lock switch off
then back on.
Turn the engine off and raise all drive wheels of the locker differential
axle in order to prevent your vehicle from moving when servicing the
wheels, tires or brakes. Axles equipped with a NoSPIN Detroit Locker
differential deliver power to both wheels even when only one wheel is on
the ground.
WARNING:Failure to raise all drive wheels with this type of
differential could cause the vehicle to move unexpectedly,
resulting in property damage, personal injury or death.
Take care to avoid sudden accelerations when both drive wheels are on a
slippery surface.
WARNING: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.
Fluid Temperature
Axle operating temperatures normally do not exceed 100°F (38°C). If
the operating temperature exceeds 230°F (110°C), the rate of axle
lubrication oxidation increases and shortens the life of the lubricant and
seals, requiring axle lubrication changes to become more frequent to
preserve the axle. Do not consistently run extreme pressure (EP)
lubricants above 230°F (110°C).
Axle Conversions
WARNING: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.
Transmission135
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
Towing173
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Installing the Axle Shafts
1. Remove the covers from the wheel ends.
2. Shift the differential lock to the unlocked (disengaged) position.
3. Install the axle shafts.
•Place the gaskets on the wheel hub studs.
•Push the right-hand axle shaft and gasket into 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 engage.
•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. See the
Workshop Manual.
174Towing
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Fuse/Relay
LocationFuse Amp
RatingProtected Circuits
16 15A High beams, Indicator
17 — Not used
18 5A Dimmer switch, Interior lighting
19 15A Engine control (diesel engine only)
20 5A Starting system
21 10A DRL resistor
22 15A Air horn, Air suspension dump, Two-speed
axle, Driver-controlled locking differential
23 10A Flasher relay
24 15A Hydraulic brakes relay, Fuel heater relay
(diesel engine only), Air dryer
25 10A Blower motor relay coil
26 10A Right-hand low beam headlight
27 — Not used
28 10A Left-hand low beam headlight
29 10A Cluster, GEM
30 15A Allison electronic transmission
31 15A Mirror fold relay
Relay 1 — Interior lamps
Relay 2 — Not used
Relay 3 — Horn
Relay 4 — Not used
Relay 5 — Not used
Fuses193
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)

Relay Center
The relay center is located along the passenger side A-pillar on the right
side of the footwell.
Relay
LocationRelay Description
R1 Spring applied hydraulic release warning chime module or
PCM power VPWR 2, 3 and 4
R2 A/C compressor clutch
R3 Power windows
R4 Flasher (standard/LED)
R5 Upfitter relay 1
R6 Upfitter relay 2
R7 Headlights
R8 Cummins starter lockout
R9 Upfitter relay 3
R10 Starter
R11 DCU (diesel engine only)
R12 Two–speed axle/Differential lock
R13 Door lock
R14 Air tank moisture valve
R15 DRL #1
R16 Heated mirrors
R17 Spare
R18 Upfitter relay 4
R1
R9 R10 R11 R12 R13 R14 R15 R16 R17
R18 R19 R20 R21 R22 R23 R24 R25 R26
R2 R3 R4 R5 R6 R7 R8
194Fuses
2015 F-650/750(f67)
Owners Guide gf(ownloose), 1st Printing, December 2013
Canadian_French(fr_can)