2010 FORD F750 light

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).
The differential lock and differential lock light will automatically
disengage at speeds above 25 mph (40 km/h). The differential lock will
remain 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.
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.
WARNING:Never shift a two-speed axle when descending a
steep grade as this may cause loss of vehicle control and result
in personal injury.
Driving
133
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

Axle shifting
Manual transmissions:
•To downshift,select the next lower gear, release and press 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.
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), then press the lower part of the
switch.
Shifting the axle from LO to HI range - vehicle moving
Accelerate to approximately 35 mph (56 km/h), 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.
LOW
2SPD
Driving
134
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

Unloaded or lightly loaded vehicles
The braking system has been designed to safely stop your vehicle when
fully loaded to its GVWR.
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.
TRAILER TOWING
Towing a trailer places an additional load on your vehicle’s engine,
transmission, axle, brakes, tires and suspension. Inspect these
components carefully prior to and after any towing operation.
Your vehicle’s load capacity is designated by weight, not by volume, so
you cannot necessarily use all available space when loading a vehicle.
2nd unit bodies are not included in maximum trailer weight ratings. The
weight of the additional “body” must be subtracted from the maximum
trailer weight.
Note:Do not exceed the GVWR or the GAWR specified on the
certification label.
WARNING:Towing trailers beyond the maximum recommended
gross trailer weight exceeds the limit of the vehicle and could
result in engine damage, transmission damage, structural damage, loss
of vehicle control, vehicle rollover and personal injury.
Model Maximum
GVWR - lb.
(kg)Maximum
GCWR - lb.
(kg)*
F-650 Regular/Super/Crew Cab 26000 (11793) 40000 (18143)
F-750 Regular/Super/Crew Cab 30000 (13608) 45000 (20412)
F-750 Regular/Super/Crew Cab 33000 (14969) 60000 (27216)
* Figures shown are the maximum available for each model. Actual
ratings may be less, depending on your transmission. Check with your
sales consultant for the exact rating on your vehicle.
Preparing to tow
Use the proper equipment for towing a trailer and make sure it is
properly attached to your vehicle. See your dealer or a reliable trailer
dealer if you require assistance.
Driving
137
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

Hitches
Do not use hitches that clamp onto the vehicle’s bumper or attach to the
axle. You must distribute the load in your trailer so that 10–15% of the
total weight of the trailer is on the tongue.
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.
WARNING: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:
•Keep your speed no faster than 70 mph (112 km/h) during the first
500 miles (800 km) of towing a trailer, and don’t make full throttle
starts.
•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.
Driving
138
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

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 opened.
•The fifth wheel is fully tilted back to prevent body damage when the
tractor is backed under a trailer.
•The trailer wheels are blocked and the trailer spring brakes are
adjusted and applied. 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, making 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. Refer toTractor-trailer connectionin theAir suspension
section of this chapter, adhering to the warning and using the three-point
stance while connecting and disconnecting the trailer.
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.
4. Be sure the coupler release lever is in the locked position.
5. Charge the trailer brake system. Set the trailer brakes, either with the
hand valve or tractor protection valve. Pull against the trailer for an
additional check of proper hook-up. Do not pull hard enough to damage
or strain the equipment.
Driving
140
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

6. Set the tractor parking brakes and fully raise the trailer landing gear.
Refer toBrakesin this chapter 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.
Driving
141
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

Passenger compartment fuse panel
Fuse/Relay
LocationFuse Amp
RatingFuse Description
1 20A Horn
2 15A Flasher relay
3 20A Cigar lighter
4 10A Data Link Connector (DLC), Engine
diagnostic connector, Parking brake warning
5 15A Blend door actuator, Function selector switch
assembly, Trailer tow relay, Trailer ABS,
Daytime Running Lights (DRL), Climate
mode, Heated seats, Exhaust brakes, Back-up
lamps switch
6 — Not used
7 — Not used
8 5A Radio, GEM
9 5A Power window switch LED and relay
10 15A Heated mirrors
11 5A Wiper and washer systems
Roadside Emergencies
144
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)

Fuse/Relay
LocationFuse Amp
RatingFuse Description
12 10A Brake pedal position switch, Transmission
shift selector, Stoplamp switch, Cruise
switches
13 20A Cluster, Radio
14 10A Interior lamp relay
15 10A Interior lamp relay, Vanity mirror lamps,
Generic Electronic Module (GEM)
16 15A High beams, Indicator
17 — Not used
18 5A Headlamp switch interior lighting
19 15A Engine control
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 Vacuum pump motor, ABS relay, Fuel heater
relay, Air dryer
25 10A Function selector switch assembly
26 10A Right hand low beam headlamp
27 — Not used
28 10A Left hand low beam headlamp
29 10A Cluster, GEM
30 15A Allison electronic transmission
31 — Not used
Relay 1 — Interior lamps
Relay 2 — Not used
Relay 3 — Horn
Relay 4 — One-touch down window
Relay 5 — Not used
Roadside Emergencies
145
2010 F-650/750(f67)
Supplement(supplement), 1st Printing
USA(fus)