2008 FORD F750 air suspension

Seating and Safety Restraints 62
Seating 62
Safety restraints 69
Child restraints 78
Driving 85
Starting 85
Brakes 92
Air suspension 113
Transmission operation 115
Vehicle loading 128
Roadside Emergencies 134
Hazard flasher switch 135
Fuses and relays 135
Jump starting 142
Wrecker towing 146
Customer Assistance 150
Getting assistance outside the U.S. and Canada 152
Ordering additional owner’s literature 153
Reporting safety defects (U.S. only) 153
Cleaning 155
Cleaning your vehicle 155
Repairing paint chips 156
Underbody preservation 158
Maintenance and Specifications 160
Hood 168
Engine oil 171
Battery 171
Engine coolant 173
Fuel information 175
Lubricant specifications 209
Refill capacities 222
Table of Contents
2
2008 F-650/750(f67)
Supplement
USA(fus)

Rear brakes
Drum:Make sure there are no cracks, dents or holes
and no loose or missing bolts. Make sure brake
linings are not worn or dangerously thin or
contaminated by lubricant.
Rear wheels
Spacers:Make sure dual wheels are evenly separated
and that tires are not touching one another.
Rims:Check for damaged or bent rims. Rims should
not have welding repairs and no rust trails that
indicate it is loose on the wheel.
Lug nuts:Make sure all lug nuts are present and not
loose (look for rust trails around the lug nuts).
There should be no cracks radiating from the
lug bolt holes or distortion of the bolt holes.
Trailer
If you are pulling a trailer, an inspection of the trailer similar to that of
the tractor should be done. Such an inspection should follow trailer
manufacturer recommendation and should include at a minimum: general
condition, landing gear, doors, sides, lights, reflectors, suspension,
brakes, tires, wheels, cargo placement, stability and tie-downs.
Transmission
If your vehicle is equipped with an automatic transmission, regularly
check the transmission’s neutral start switch. The engine should only
start in the N (Neutral) or P (Park) positions.
If the unit starts in gear and/or the neutral start switch is not
functioning correctly, the vehicle may inadvertently move which
could result in property damage, personal injury or death.
Check the transmission fluid level and shift linkage for proper operation.
2008 F-650/750(f67)
Supplement
USA(fus)
Vehicle Inspection Guide
20

WARNING LIGHTS AND CHIMES
Warning lights and gauges can alert you to a vehicle condition that may
become serious enough to cause expensive repairs. A warning light may
illuminate when a problem exists with one of your vehicle’s functions.
Many lights will illuminate when you start your vehicle to make sure the
bulb works. If any light remains on after starting the vehicle, have the
respective system inspected immediately.
Some of the warning lights shown are optional based on vehicle
equipment; your vehicle may not have some of the warning lights shown
in this section.
Service engine soon:If this light
illuminates while driving, it is a
possible indication that one of the
engine’s emission control systems
has failed.
Check suspension (if equipped):
Illuminates when the air suspension
dump switch has been activated.
SERVICE
ENGINE
SOON
2008 F-650/750(f67)
Supplement
USA(fus)
Instrument Cluster
21

Air pressure gauge:All vehicles
equipped with air brakes have a
dual-pointer air gauge to indicate
the pressure in each brake circuit.
The green pointer indicates the air
pressure in the primary system and
the red pointer indicates the air
pressure in the secondary system.
When the pressure is too low for
normal brake operation (less than
60 psi [414 kPa]) and the ignition is
on:
•a warning buzzer will sound and
•a warning light will illuminate in the instrument cluster
Do not drive the vehicle when the low air pressure buzzer is
sounding or the warning light is lit. These warnings indicate
there is not enough air pressure for the brake or suspension system to
operate properly.
Vehicles equipped with hydraulic brakes and an air compressor have a
single-pointer air gauge.
Note:This system doesnothave a low air pressure warning buzzer or a
low air pressure warning light.
0 30120 90 60
150AIR
PRESSURE
PSI
2008 F-650/750(f67)
Supplement
USA(fus)
Instrument Cluster
31

Aggressive driving in any road conditions can cause you to lose
control of your vehicle increasing the risk of severe personal
injury or property damage. The occurrence of a Traction Control
event is an indication that at least some of the tires have exceeded
their ability to grip the road; this may lead to an increased risk of loss
of vehicle control, vehicle rollover, personal injury and death. If you
experience a severe road event, SLOW DOWN.
AIR SUSPENSION (IF EQUIPPED)
Note:The vehicle must not be operated without air in the suspension
springs. Operating the vehicle without air in the air suspension springs
will damage the suspension, degrade ride performance and may cause
property damage.
The suspension system automatically adjusts to different loads to
maintain a constant frame height. The system allows for ease of vehicle
loading and provides improved vehicle ride and increased driver comfort.
Air suspension dump switch
The system is controlled by a switch
located on the instrument panel.
The switch will operate only when
the ignition is in the ACC
(Accessory) or IGNITION positions
and the air tanks have sufficient
pressure to fill the air springs. When
the ignition is turned off, the
suspension will remain in whatever
state it was last set.
Note:The suspension will dump air when the ignition is in the ACC or
IGNITION position, but will only fill when the ignition is in the IGNITION
position.
When the upper portion of the switch is pressed air supplied to the air
spring is exhausted, lowering the frame for loading. Pressing the lower
portion of the switch causes air to fill the air springs so the vehicle will
remain at normal ride height.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
113

Tractor-trailer connections
To reduce the risk of personal injury, use extreme caution when
making brake and light connections. Inclement weather and
accumulated road contamination deposits on handhold and stepping
surfaces require extra care to avoid slip and falls. Provide adequate
lighting of working areas.
Do not climb on the back of the tractor unless it has been
provided with a deck plate and handholds. Use a three-point
stance when climbing up and down from a deck plate. Do not jump
from the vehicle. Whenever possible, make all connections while
standing on the ground.
Connecting and disconnecting a trailer with air suspension
When connecting to a trailer:
•Press the lower portion of the switch and air will exhaust from the air
suspension system.
•After making the connection to the trailer, press the upper portion of
the switch, then raise the landing gear.
When disconnecting the trailer:
•Lower the landing gear, then press the lower portion of the switch.
•Disconnect the brake hoses, trailer-side and rear light connectors,
then pull the release lever on the fifth wheel.
The upper portion of the switch must be pressed before operating with a
trailer or operating in the bobtail mode.
Suspension conversions
It is not recommended, or approved, that suspension conversions be
performed. However, it is understood that, on occasion, aftermarket
add-on suspensions 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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
114

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.
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.
2008 F-650/750(f67)
Supplement
USA(fus)
Driving
132

Fuse/Relay
LocationFuse Amp
RatingFuse Description
15 10A Interior lamp relay, GEM, Vanity mirrors
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
24 15A ABS, Air dryer, Vacuum pump, Fuel heater
relay
25 10A Function selector switch
26 10A RH low beam headlamp
27 — Not used
28 10A LH low beam headlamp
29 10A Cluster warning lamps, Gauges, GEM,
Hydraulic ABS
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
Power distribution box
Always disconnect the battery before servicing high current
fuses.
2008 F-650/750(f67)
Supplement
USA(fus)
Roadside Emergencies
137