Page 60 of 273
To set a higher set speed
Press and hold SET +. If the vehicle
is moving, this will increase vehicle
speed; if the vehicle is stationary,
this will increase engine RPM.
Release the control when the
desired vehicle speed/engine RPM is
reached.
Press and release SET + to operate
the tap-up function. Each press will increase the set speed by 1 mph
(1.6 km/h) or engine RPM in idle mode.
To set a lower set speed
Press and hold RESUME -. If the
vehicle is moving, this will decrease
vehicle speed; if the vehicle is
stationary, this will decrease engine
RPM. Release the control when the
desired vehicle speed/engine RPM is
reached.
Press and release RESUME - to
operate the tap-down function. Each press will decrease the set speed in
increments of 1 mph (1.6 km/h) or engine RPM in idle mode.
SET RESUME
2008 F-650/750(f67)
Supplement
USA(fus)
Driver Controls
59
Page 61 of 273
To disengage speed control
•Depress the brake pedal or
•Depress the clutch pedal (if
equipped).
Disengaging the speed control will
not erase the previously
programmed set speed or engine
RPM.
Pressing OFF will erase the
previously programmed engine RPM.
CRUISE
RPM
OFF
2008 F-650/750(f67)
Supplement
USA(fus)
Driver Controls
60
Page 62 of 273
To return to a previously set speed
Press RESUME -. For RESUME - to
operate, the vehicle speed must be
above 30 mph (48 km/h) or engine
speed must be above 1,000 RPM.
KEYS
The key operates all locks on your vehicle. In case of loss, replacement
keys are available from your dealer.
You should always carry a second key with you in a safe place in case
you require it in an emergency.
POWER DOOR LOCKS (IF EQUIPPED)
Press U to unlock all doors and L to
lock all doors.
SET RESUME
U L
2008 F-650/750(f67)
Supplement
USA(fus)
Locks and Security
61
Page 78 of 273

•The driver’s safety belt is unbuckled.
•The headlamp control is in the
position.
While the design allows you to deactivate your Belt-Minder,this
system is designed to improve your chances of being safely
belted and surviving an accident. We recommend you leave the
Belt-Mindersystem activated for yourself and others who may use the
vehicle. To reduce the risk of injury, do not deactivate/activate the
Belt-Minderfeature while driving the vehicle.
Belt-Minderactivation and deactivation procedure
1. Turn the ignition switch to the RUN (or ON) position. (DO NOT
START THE ENGINE.)
2. Wait until the safety belt warning light turns off. (Approximately 1–2
minutes.)
•Steps 3–5 must be completed within 60 seconds or the procedure will
have to be repeated.
3. Buckle then unbuckle the safety belt three times, ending with the
safety belt unbuckled. This can be done before or during Belt-Minder
warning activation.
4. Turn on the parklamps/headlamps, turn off the parklamps/headlamps.
5. Buckle then unbuckle the safety belt three times, ending with the
safety belt unbuckled.
•After step 5 the safety belt warning light will be turned on for three
seconds.
6. Within seven seconds of the safety belt warning light turning off,
buckle then unbuckle the safety belt.
•This will disable Belt-Minderif it is currently enabled, or enable
Belt-Minderif it is currently disabled.
7. Confirmation of disabling Belt-Minderis provided by the safety belt
warning light flashing four times per second for three seconds.
8. Confirmation of enabling Belt-Minderis provided by:
•The safety belt warning light flashing four times per second for three
seconds.
•Followed by three seconds with the safety belt warning light off.
•Once again, the safety belt warning light will flash four times per
second for three seconds.
2008 F-650/750(f67)
Supplement
USA(fus)
Seating and Safety Restraints
77
Page 86 of 273

STARTING
Positions of the ignition
1. ACCESSORY, allows the electrical
accessories such as the radio to
operate while the engine is not
running.
2. LOCK, locks the steering wheel,
automatic transmission gearshift
lever and allows key removal.
3. OFF, shuts off the engine and all
accessories without locking the
steering wheel.
4. ON, all electrical circuits operational. Warning lights illuminated. Key
position when driving.
5. START, cranks the engine. Release the key as soon as the engine
starts.
Starting the engine
Operation of a diesel engine near flammable vapors in the air
may cause the engine speed to increase uncontrollably and over
speed. If this situation occurs, mechanical damage, fire, explosion,
personal injury or death could result.Turning off the ignition key
will not slow or stop the engine due to uncontrollable fueling of the
engine through flammable vapors being drawn into the engine air
inlet.Operation of components such as starter, alternator, electric
motors, etc. and static electricity could also ignite flammable vapors.
Do not operate the truck in the possible presence of flammable vapors
unless both a complete hazard analysis is performed and necessary
additional safety processes and/or equipment such as vapor testing, air
intake shutoff devices, ventilation, etc. are utilized. The operator is
responsible for using those processes and/or equipment to ensure that
the diesel engine and all other components on the truck can be
operated safely under the specific conditions and hazards that may be
encountered.
3
1
2
5
4
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
85
Page 87 of 273

Note:When starting the engine, do not press the accelerator as engine
damage may result.
1. Ensure headlamps and all accessories are turned off, the parking
brake is applied and the transmission is in the neutral position (or P
[Park] for Allison 2200 transmissions).
2. Turn the key to ON, but do not start the engine. In cooler weather,
the air intake heater may activate the WAIT TO START light in the
instrument cluster.
If the WAIT TO START light
illuminates,do notcrank the engine
until the light goes off.
If equipped with an air intake heater, DO NOT use ether or any
other starting fluids. The use of starting fluids (ether) in an
engine equipped with an air intake heater could cause an explosion
and result in property damage and/or personal injury.
3. When the WAIT TO START light turns off, turn the key to START;
when the engine starts, release the key.
If the engine does not start after 30 seconds of cranking, allow two
minutes for the starter to cool before trying again. Excessive cranking
may damage the starter.
After the engine starts:
•On some engines, the WAIT TO
START light should illuminate
after the engine starts. Allow the
engine to idle about three
minutes or until the engine
coolant temperature gauge begins to rise. Maintain idle speed until the
WAIT TO START light cycles off to indicate the air intake heater has
shut off (approximately six minutes). Operating the engine at higher
speeds will reduce the effectiveness of the air inlet heater.
WAIT
TO
START
WAIT
TO
START
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
86
Page 88 of 273

•Do not increase engine speed
until the oil pressure gauge
indicates normal pressure; this
should be indicated on the gauge
within 15 seconds after starting.
•Idle the engine for three to five
minutes before operating with a
full load.
•Try to limit engine idle to 10
minutes. Excessive idling reduces
fuel economy.
•When starting a cold engine, increase the engine speed (RPM) slowly
to make sure adequate lubrication is available to the bearings.
Cold weather operation
Do not use volatile starting aids such as ether, propane or
gasoline in the engine air intake system. Glow plugs may ignite
vapors which can cause engine damage or personal injury.
In order to operate the engine in temperatures of 32°F (0°C) or lower,
read the following instructions:
•Make sure that the batteries are of sufficient size and are fully
charged. Check other electrical components to make sure they’re in
optimum condition.
•Use a permanent-type engine coolant solution to protect the engine
against damage from freezing.
•If your vehicle is equipped with a water-fuel separator, drain it daily.
Fill the fuel tank at the end of daily operation to prevent condensation
in the fuel system.
•Make sure you use proper cold weather engine oil and that it is at its
proper level.
•At temperatures of –4°F (–20°C) or below, it is recommended that you
use a crankcase-mounted coolant heater to improve cold engine
starting.
•If operating in arctic temperatures of –20°F (–29°C) or lower, consult
your truck dealer for information about special cold weather
equipment and precautions.
Note:Idling in cold weather will not heat the engine to its normal
operating temperature. Long periods of idling in cold weather can cause
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
87
Page 89 of 273

a buildup of heavy deposits of carbon and rust on valve stems causing
them to stick which, in turn, can cause valvetrain damage.
Winter fronts
The use of winter fronts, or other air-restrictive devices mounted in front
of the radiator on vehicles with chassis-mounted charge air coolers, are
not recommended unless extremely cold weather conditions exist. Air
flow restriction can cause high exhaust temperatures, power loss,
excessive fan usage and a reduction in fuel economy. If you must use a
winter front, the device should have a permanent opening of at least 120
sq in. (774 sq. cm) directly in line with the fan hub.
Hot weather operation
•Keep the engine cooling system filled with a clean, permanent coolant
solution to protect against damage from overheating.
•Fill the fuel tank at the end of daily operation to prevent condensation
in the fuel system.
•Keep external surfaces of the engine, radiator, charge air cooler, A/C
condenser and accessories clean to avoid dirt build-up.
Above normal coolant temperatures could be experienced while driving
in a transmission gear ratio which lugs the engine. To correct this
problem, engine speed should be increased by downshifting in to the
next lower gear to increase engine RPM.
Starting a turbocharged engine with the vehicle on a steep grade
When starting a diesel engine when the loaded vehicle is on a grade, the
engine RPM will start to fall slightly when the clutch is engaged; do not
disengage the clutch and try to increase engine RPM as this may damage
driveline components. The engine will recover as the vehicle begins
moving.
Engine shutdown
Allow the engine to idle for three to five minutes before shutting it
down. The larger the engine, the greater the need for this idling period.
However, do not let the engine idle for more than 10 minutes.
Restarting after running out of fuel
The fuel system may need to be purged of air, refer toRunning out of
fuelin theMaintenance and Specificationschapter.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
88