flat tire FORD F750 2003 10.G Owners Manual

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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•10–hole disc
•8–hole disc
Always tighten wheel lug nuts
alternately in the sequence shown.
Make sure the wheel is drawn
evenly against the hub or drum.
Check for damage that would affect
the runout of the wheels. Wobble or
shimmy caused by a damaged wheel
will eventually damage the wheel
bearings. Stones or lumps of mud
wedged between a wheel and drum
or between dual wheels can unbalance a wheel and tire.
Servicing your tires
Inspect the tire treads and remove stones, nails, glass or other objects
that may be wedged in the tread grooves. Check for holes or cuts that
may permit air leakage from the tire and make the necessary repairs.
Inspect the tire sidewalls for cuts, bruises and other damage. If internal
damage to the tire is suspected, have the tire removed from wheel and
inspected.
Check the pressure regularly. Maintain the recommended air pressure for
your vehicle, load, tires and rims or wheels. Check the tire valve for air
leaks and replace the valve if necessary. If the valve cap is missing,
install a new cap. Refer toTire/Wheel Rim Selection and Inflation
Pressuresor theVehicle Certification Labelin this chapter.
5310
1
8
6
4
9 2 7
1
3 4
27 6
5 8
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212

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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213

ADD and FULL marks indicated on the hub. Do not overfill. Overfilling
can result in oil on brake linings.
Refer to your general maintenance information section for fluid level
checks and change intervals for the front hubs.
Your front hubs may be filled with an optional synthetic fluid which
allows use of the extended service intervals. A green colored filler plug
identifies use of the synthetic fluid.
Tire/wheel rim selection and inflation pressures
Tire Size, Load
Range (PR)Wheel Width
(in.) and TypeSingle Rear Axle: Max. Tire
and Wheel Capacity kg. (lb.)
kPa @ (psi) (cold) by Axle
Tubeless Type Radial Ply Front Rear
10R22.5 F (12) 7.50 10H
(I.S.O.)10 300 (4 671)
698 10019 280 (8 745)
698 100
10R22.5 G (14) 7.50 10H
(I.S.O.)10 300 (4 671)
698 10021 000 (9 525)
711 115
11R22.5 G (14) 8.25 10H
(I.S.O.)12 080 (5 478)
703 10522 520 (10 213)
703 105
245/70R19.5 6.75 8H (I.S.O.) 10 300 (4 671)
698 10019 280 (8 745)
698 100
11X20 (16) 7.50 10H
(I.S.O.)12 080 (5 478)
703 10522 520 (10 213)
703 105
MINOR TROUBLESHOOTING GUIDE
Diesel engine
For troubleshooting information, refer to the diesel engine operator’s
manual.
If engine won’t crank
For troubleshooting information, refer to the engine operator’s manual.
If engine cranks but won’t start
For troubleshooting information, refer to the engine operator’s manual.
If engine runs hot
For troubleshooting information, refer to the engine operator’s manual.
Maintenance and Specifications
214