2003 FORD F750 steering

Drain all the air brake reservoirs
daily, completely to 0 kPa/psi, by
opening the draincock at the bottom
of the tanks. Close draincock after
complete draining. Air tanks
equipped with automatic moisture
ejector valves may also be drained
manually as required to maintain a
dry air system. Contact your dealer
if you are unsure of the air reservoir
locations or the draining procedure.
STEERING
Your vehicle is equipped with power steering. Power steering uses energy
from the engine to decrease the driver’s effort in steering the vehicle.
Never hold the steering wheel to the extreme right or the extreme left
for more than a few seconds when the engine is running. This action
could damage the power steering pump.
Suspension and steering
The suspension and steering linkage in your vehicle should be inspected
periodically for the following:
•Spring leaf damage
•Spring sag
•Abnormal looseness
•Damaged seals
The following changes indicate a need to inspect and service your
vehicle:
•Changes in steering action
•Hard steering
•Excessive free play
•Unusual sounds when turning or parking
If the steering wanders or pulls
This condition can be caused by any of the following conditions:
•Underinflated tire(s) on any wheel(s)
•Front end out of alignment
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•Total vehicle out of alignment (i.e. rear axle[s] out of alignment with
front axle)
•Improper adjustment in the steering gear
•Vehicle overloaded or unevenly loaded
•High crosswinds
•High crown in center of road
•Components in steering linkage loose or worn
•Wheel bearings improperly adjusted
•Excessive lash in steering shaft or universal joints
If the vehicle steers hard
Hard steering can be caused by any of the following conditions:
•Underinflated tire(s) on any wheel(s)
•Vehicle overload
•Misalignment of the front tires
•Lack of lubricant in the front spindle bearings or linkage components
•Low oil level in the power steering system
•Broken or loose power steering pump direct drive connection
•Malfunctioning relief valve in power steering gear or steering pump
•Malfunctioning power steering pump
•Restriction in power steering lines
•Improperly set turn stops
•Air entrapped in power steering system fluid
AIR SUSPENSION SYSTEM (IF EQUIPPED)
The on-highway air suspension system is designed to provide a superior
ride, outstanding driver comfort while minimizing wear on the cab, frame
and payload.
The height control valve automatically keeps the vehicle at a constant
level due to load changes and uneven road surfaces.
Air suspension-equipped vehicles are equipped with a dryer module
which needs to be opened monthly to remove moisture from the system.
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•The hazard lights control is
located on top of the steering
column.
•Depress hazard lights control to
activate all hazard flashers
simultaneously.
•Depress control again to turn the
flashers off.
FUSES AND RELAYS
Fuses
If electrical components in the
vehicle are not working, a fuse may
have blown. Blown fuses are
identified by a broken wire within
the fuse. Check the appropriate
fuses before replacing any electrical
components.
Note:Always replace a fuse with one that has the specified amperage
rating. Using a fuse with a higher amperage rating can cause severe wire
damage and could start a fire.
Standard fuse amperage rating and color
COLOR
Fuse
ratingMini
fusesStandard
fusesMaxi
fusesCartridge
maxi
fusesFuse link
cartridge
2A Grey Grey———
3A Violet Violet———
4A Pink Pink———
5A Tan Tan———
7.5A Brown Brown———
10A Red Red———
15A Blue Blue———
20A Yellow Yellow Yellow Blue Blue
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151

COLOR
Fuse
ratingMini
fusesStandard
fusesMaxi
fusesCartridge
maxi
fusesFuse link
cartridge
25A Natural Natural———
30A Green Green Green Pink Pink
40A——Orange Green Green
50A——Red Red Red
60A——Blue—Yellow
70A——Ta n—Brown
80A——Natural—Black
Passenger compartment fuse panel
The fuse panel is located below and to the left of the steering wheel by
the brake pedal. Remove the panel cover to access the fuses.
To remove a fuse use the fuse puller tool provided on the fuse panel
cover.
Relay #1
Relay #2
Relay #3
Horn
Relay #4
Relay #5 One Touch
Down Interior
Lamps#1
#12#22
#2
#3
#4
#5
#6
#7
#8
#9
#10
#11#13
#23
#14
#15
#16
#17#24
#25
#26
#27
#18
#28
#19
#29
#20
#21#30
#31
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152

Do not operate the starter longer than 30 seconds. Wait at least
two minutes between starting attempts to allow the starter to
cool. If the engine does not start after several attempts, call for
road service.
Removing the jumper cables
1. Remove the ground connection
from the disabled vehicle first,
followed by the cable on the
negative (-) battery terminal of the
booster vehicle.
2. Remove the cable from the
positive (+) terminal of the
discharged battery and then from
the positive (+) terminal of the
booster battery.
3. After the disabled vehicle has
been started, allow it to idle for a
while so the engine can“relearn”its
idle conditions.
WRECKER TOWING
Always unload your vehicle before towing it. The recommended method
of towing is with the drive wheels off the ground.
Before towing, make sure:
•the parking brake is released.
•if air pressure has been lost, to release the brakes manually.
Improper towing of the vehicle will not allow sufficient lubrication of the
transmission which may cause serious damage to internal transmission
components. Always follow the outlined towing procedures.
•To tow a vehicle on the front wheels,the steering wheel must be
in the straight ahead position. Secure the steering wheel with a
holding device (such as provided by a towing company).
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CHECKING AND ADDING POWER STEERING FLUID
Checking power steering fluid level
Check the power steering fluid level using the following procedure. Refer
to the general maintenance information section for the recommended
service intervals. If adding fluid is necessary, use only MERCONAT F.
1. Set the parking brake, shift into N
(Neutral) (automatic transmission)
or 1 (First) (manual transmission)
and turn the engine off.
2. Open the hood.
3. Clean the top of the power
steering fluid reservoir.
4. Remove the dipstick from the
reservoir and wipe the dipstick
clean.
5. Reinstall the dipstick. Remove it again and check the fluid level.
•If the fluid temperature is at
approximately 20°C-49°C (68°F
- 120°F) (fluid cool or warm to
the touch), check the COLD side
of the dipstick. The fluid level
should be within the FULL range
•If the fluid level is below the ADD
line, add fluid in small amounts,
continuously checking the level until it reaches the proper level.
•If the fluid temperature is at
approximately 80°C - 110°C
(176°F - 230°F) (fluid too hot
to touch), check the HOT side of
the dipstick. The fluid level
should be within the FULL range.
•If the fluid level is below the ADD
line, add fluid in small amounts,
continuously checking the level until it reaches the proper level.
A low fluid level may indicate a leak in the power steering system.
Inspect the power steering system and repair the leak. If necessary, see
your dealer or a qualified service technician.
ADD MAX. COLDFULL
ADD MAX. HOTFULL
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201

To avoid damage to the power steering system,do notoperate the
vehicle with a low power steering fluid level.
Whenever the dipstick is installed, make sure it is properly seated and
tightened securely.
CLUTCH FLUID (IF EQUIPPED)
Check the clutch fluid level. Refer to the general maintenance
information section for the service interval schedules.
During normal operation, the fluid level in the clutch reservoir should
remain constant. If the fluid level drops, maintain the fluid level at the
step in the reservoir.
Use only a DOT 3 brake fluid designed to meet Ford specifications. Refer
toLubricant Specificationsin this chapter.
1. Set the parking brake, shift into 1
(First) and turn the engine off.
2. Open the hood.
3. Clean the reservoir cap before
removal to prevent dirt and water
from entering the reservoir.
4. Remove cap and rubber
diaphragm from reservoir.
5. Add fluid until the level reaches
the step in the reservoir.
6. Reinstall rubber diaphragm and cap onto reservoir.
Clutch (if equipped)—linkage lubrication
Lubricate the clutch linkage using the following procedure. Refer to the
general maintenance information section for the service interval
schedules.
Use a grease which meets Ford specifications. Refer toLubricant
Specificationsin this chapter.
1. Set the parking brake, shift into 1 (First) and turn the engine off.
2. Remove the inspection cover from the clutch housing.
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202

An inflated tire and rim can be very dangerous if improperly
used, serviced or maintained. To avoid serious injury, never
attempt to re-inflate a tire which has been run flat or seriously
under-inflated without first removing the tire from the wheel assembly
for inspection. Do not attempt to add air to tires or replace tires or
wheels without first taking precautions to protect persons and
property.
Refer to the Ford Service Manual or the regulations of the Occupational
Safety and Health Administration (OSHA) for appropriate procedures
and cautions.
Tire inflation pressure must not exceed the recommendations of
the axle, tire and/or wheel rim manufacturer for the specific
load, speed and application. The inflation pressures on the tire sidewall
do not take the wheel rim capabilities into consideration.
Never use a rim of different manufacture or any different size or
type than original rims.
Try to replace tires in pairs on the same axle shaft. Tires larger or
smaller than originally installed may affect the accuracy of the
speedometer. Consult your dealer about the need to change the switch
setting on the back of the speedometer.
Front wheel alignment
If abnormal tire wear or ride and handling characteristics such as vehicle
lead or wander are experienced with properly inflated tires, the front
end alignment should be checked.
Wheel bearing care
Front and rear wheel bearings are adjustable to correct for bearing and
spindle wear. Long bearing life depends upon proper adjustment and
correct lubrication. If bearings are adjusted too tightly (preloaded) they
will overheat and wear rapidly. Loose adjustment will cause pounding
and will contribute to uneven tire wear, steering difficulties and
inefficient brake operation.
Refer to the Ford Service Manual applicable to your vehicle for proper
tightening procedures and torque specifications.
Periodically check the oil level on oil filled front bearing hubs. If
necessary, add oil through the filler plug so the oil level is between the
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