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TRUCK SERVICE MANUAL 
TM 5-4210-230-14&P-1
STEERING GEAR
NORMAL NOISE
1.    A   "hissing"   noise   may   be   heard   from   the   control
valve when it is actuated during a steering maneuver.
2.    Fluid  being  bypassed  thru  the  poppets  at  full  turn
may cause noise.
3.    Noise  may  be   heard   from   the   system   relief   valve
when it is required to actuate.
4.    Pump   "growl"   may   be   heard   from   some   types   of
power steering pumps.
ABNORMAL NOISE
1.
If    the    power    steering    pump    is    belt    driven,    a
"squealing"  noise  during  steering  may  indicate  that
the belt(s) should be tightened or replaced.
2.    A   "clicking"   noise   heard   when   initiating   a   steering
maneuver  or  when  changing  directions  of  turn  may
indicate that some component is loose and is shifting
under load.
3.    A    change    in    the    normal    noise    from    the    power
steering    pump    may    indicate    that    an    excessive
amount of air has been trapped in the fluid or that the
fluid level is low.  Also check for dirt, sludge, or other
foreign   material-trapped   in   filter,   screen,   or   other
passages in the hydraulic system.
4.    Excessive  noise  from  the  power  steering  pump  may
indicate   that   it   is   worn   or   defective.      See   "Pump
Pressure Test" and Pump Flow Test.
ROAD WANDER
1.    Components in steering linkage such as ball sockets
on drag link or axle arm loose or worn.
2.    Tire pressure incorrect or unequal left to right.
3.    Wheel bearings improperly adjusted or worn.
4.    Steering gear mounting bolts loose on frame.
5.    Front end alignment out of specification.
6.    Steering gear center adjustment improperly adjusted.
(See adjustment procedure)
7.     Dry fifth wheel or poor finish on fifth wheel or trailer
plate.
8.    Steering geometry incorrect (pitman arm and/or axle
arm ball position).
9.    Worm preload improperly adjusted.  (See adjustment
procedure).
NO RECOVERY
1.    Front end alignment incorrect.
2.    Ball sockets or other linkage connections too tight or
not lubricated.
3.    Pump Flow insufficient.
4.    Tire pressure low.
5.    Fifth wheel dry.
6.    Control valve spool or sleeve sticking.
7.    Tight front axle spindles.
8.    Steering column binding.
9.    Sector  shaft  adjustment  too  tight.    (See  adjustment
procedure).
10.    Worm preload too tight.
SHIMMY
1.    Front end alignment incorrect.
2.    Air in hydraulic system.
3.    Wheels out of balance.
4.    Components in steering linkage such as ball sockets
on drag link or axle arm loose or worn.
5.    Badly worn or unevenly worn tires.
6.    Wheel bearings improperly adjusted or worn.
EXTERNAL OIL LEAKAGE
1.    No external leakage is acceptable at steering gear.
2.    Rubber relief plug (60) leaking at side cover indicates
failure of sector shaft oiloseal (54) in side cover.
3.    Finding location of leak may be difficult since oil may
"run" away from leak and drip from a low point on the
gear or chassis.
DARTING OR TENDENCY TO OVERCORRECT 1
1.    Front end components binding.
2.    Sector   shaft   adjustment   too   tight   (see   adjustment
procedure).
3.    Control valve spool or sleeve sticking.
4.    Steering geometry incorrect (pitman arm and/or axle
arm ball position).
5.    Steering column binding.
HIGH STEERING EFFORT
1.    Vehicle overloaded.
2.    Inadequate flow (See Pump Flow Test)
3.    Inadequate pressure (See Pump Pressure Test).
4.    Excessive   internal   leakage   in   steering   gear   (see
Steering Gear Internal Leakage Test).
5.    Low hydraulic fluid level.
6.    Low tire pressure.
7.    Restriction in supply line or supply line too small.
8.    High  back  pressure  caused  by  restriction  in  return
line or clogged filter. .
9.    Binding  or  lack  of  lubrication  in  linkage  components
or in steering column.
10.    Poppet   adjustment   improper   (if   high   effort   occurs
near  end  of  travel  in  one  or  both  directions  of  turn
CTS-2717   Page 17
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