If the steering wanders or pulls
This condition can be caused by any of the following conditions:
²Underinflated tire(s) on any wheel(s)
²Front end out of alignment
²Total vehicle out of alignment (i.e. rear axle[s] out of alignment with
front axle)
²Improper adjustment in the steering gear
²Vehicle overloaded or unevenly loaded
²High crosswinds
²High crown in center of road
²Components in steering linkage loose or worn
²Wheel bearings improperly adjusted
²Excessive lash in steering shaft or universal joints
If the vehicle steers hard
Hard steering can be caused by any of the following conditions:
²Underinflated tire(s) on any wheel(s)
²Vehicle overload
²Misalignment of the front tires
²Lack of lubricant in the front spindle bearings or linkage components
²Low oil level in the power steering system
²Broken or loose power steering pump direct drive connection
²Malfunctioning relief valve in power steering gear or steering pump
²Malfunctioning power steering pump
²Restriction in power steering lines
²Improperly set turn stops
²Air 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.
Driving
125
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
ADD and FULL marks indicated on the hub. Do not overfill. Overfilling
can result in oil on brake linings.
Refer to your Scheduled Maintenance Guide 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.
Maintenance and care
182
Maintenance Operation Frequency - Observation
Inspect the automatic slack
adjuster functionInsufficient power shown in loaded
practice stop
Check the operation of the
brakes, the clutch, and the
steering (*b,a)Vehicle handling qualities not up to
par
Inspect the vehicle for missing,
damaged, or mislocated noise
shieldsExcessive noise emanates from under
the cab or engine compartment
Check the engine performance
and the engine governorExcessive engine noise
Inspect the fan, the fan shroud,
and the fan clutchEngine overheats, fans runs at high
speed constantly, excessive fan noise,
or fan wobble due to worn bearings
Check for operation of ABS
warning lampAt each engine start up
Inspect the entire exhaust
system (including inlet pipe,
muffler, outlet pipe and all
exhaust clamps and fasteners)
for holes, leakage, breakage,
looseness and corrosive
damageExcessive noise or the smell of fumes
is experienced
Inspect the engine air
induction system (including the
air ducts, the air cleaner, and
the air cleaner element) for
loose fitting, damaged or
missing componentsExcessive noise emanates from the
engine compartment
Inspect the tires and check the
air pressure (*c)Poor steering, wandering or excessive
tire wear
Balance the wheels and the
tiresVibration or abnormal tire wear
indicates imbalance
Check the front end alignment
(*c)Poor steering, wandering or excessive
tire wear
Check the transmission and
engine mountings (*b)Hard shifting or excessive vibration
General maintenance information
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