2012 FORD F650 differential

Diesel particulate filter (diesel
engine only):Illuminates when the
soot level in the DPF has reached a
point where it requires operator
assistance. Refer toDiesel
particulate filterin the
Maintenance and Specifications
chapter and your engine operator’s
manual, for more details.
Do not shift (Allison automatic
transmission only):Illuminates
while driving if a problem has been
detected and shifting may be
restricted. Depending upon the
severity of the problem, the
read-out digit on the shifter display
may be blank. Operation may
continue in order to reach service assistance. The ECU may not respond
to shift selector requests, since operating limitations are being placed on
the transmission, i.e. upshifts and downshifts may be restricted.
Direction changes do not occur.
Refer to your transmission operator’s manual for more information.
Electronic locking differential
(if equipped):Displays when using
the electronic locking differential.
Engine oil pressure (gasoline
engine only):Illuminates when
engine oil pressure is low.
High beams:Illuminates when the
high-beam headlamps are turned on.
Instrument Cluster
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Supplement, 2nd Printing
USA(fus)

REAR AXLE INFORMATION
Axle operating temperature normally don’t exceed 100°F (38°C). If the
operating temperature exceeds 230°F (110°C), the rate of axle
lubrication oxidation increases and shorten the life of the lubricant and
seals, requiring axle lubrication changes to become more frequent to
preserve the axle. Extreme Pressure (EP) lubricants should not be run
consistently above 230°F (110°C).
Gross axle weight
Your truck has gross axle weight, gross vehicle weight and gross
combination weight ratings. Do not exceed these ratings.
WARNING:Exceeding these ratings by overloading can cause
component failure resulting in property damage, personal injury
or death.
Rear axles with locking or limited-slip differentials (if equipped)
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 the vehicle stationary.
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
Driver-controlled differential lock
To prevent the vehicle from moving when servicing the wheels, tires or
brakes, turn the engine off and raise all drive wheels of the locker
differential axle. Axles equipped with NoSPIN Detroit Locker differentials
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.
Driving
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Care should be taken 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.
Some 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
provides full power to both axles.
When the differential is locked, the vehicle’s turning radius increases
(vehicle “under-steers”).
The differential can be locked or unlocked when the vehicle is moving at
a constant speed of under 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).
The differential lock and differential lock light automatically disengage at
speeds above 25 mph (40 km/h). The differential lock remains off until
either the vehicle is restarted or the differential lock switch is turned off
then back on.
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).
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.
Driving
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USA(fus)

Fuse/Relay
locationFuse amp
ratingFuse description
15 10A Interior lamp relay
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
Roadside Emergencies
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Relay
locationRelay description
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
R19 Shift interlock/EPRNDL display
R20 Selective Catalyst Reduction (SCR) system (NOx) (diesel
engine only)
R21 Run
R22 Door unlock
R23 ABS warning indicator
R24 DRL #2
R25 Park lights
R26 Spare
Roadside Emergencies
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4. Remove the jumper cable from the positive (+) terminal of the
disabled vehicle’s battery.
After the disabled vehicle has been started and the jumper cables
removed, allow it to idle for several minutes so the engine computer can
relearnits idle conditions.
WRECKER TOWING INSTRUCTIONS
Before moving the disabled vehicle, check for adequate road clearance of
vehicle components. It is recommended the disabled vehicle be unloaded
prior to being towed to reduce any abnormal load to the vehicle
components resulting from the towing procedures. Before towing, be sure to
fully release the parking brake. The spring-actuated type parking brake can
be reset by recharging the air system with at least 64 psi (441 kPa) of air. If
the brake system does not retain air pressure, then the spring brakes must
be released manually. Refer toParking brakein theDrivingchapter.
Note:For towing, make sure the vehicle is securely connected to the
tow vehicle and the tow vehicle’s parking brakes are applied before
releasing the disabled vehicle’s spring brakes.
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.
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:
•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 driveshaft is required.
+–+–
Roadside Emergencies
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Note:To avoid transmission damage, vehicles should not be towed even
a short distance without suspending rear wheels or removing the axle
shafts or driveshaft.
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.
1. Shift collar in the locked position
2. Actuator assembly and shift fork
3. Axle shaft
4. Interference between the shift
collar and housing
5. Shift collar in the unlocked
position
6. Outer splines - axle shaft to collar
7. Shift collar and differential case
splines
8. Inner splines - axle shaft to side
gear
9. Side gear
10. Differential (plain) case half
Roadside Emergencies
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USA(fus)

Removing axle shafts before towing
1. Shift the main differential to the unlocked (disengaged) position; the
differential lock light turns off.
2. Remove the capscrews 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 wheels 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.
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 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.
Roadside Emergencies
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USA(fus)