GMC 1986 P-Truck Service Manual page 185

The following " Notice" applies to one or more steps in the assembly procedure of components in this portion of
the manual as indicated at appropriate locations by the terminology: " NOTICE: See 'Notice' on page 3B1-1 of this
section."
NOTICE: All steering linkage fasteners are im portant attaching parts in that they could affect the perform ­
ance o f vital parts and systems, and/or could result in major repair expense. They must be replaced w ith one
o f the same part num ber o r w ith an equivalent part if replacement becomes necessary. Do not use a replace­
ment part o f lesser quality or substitute design. Torque values must be used as specified during reassembly
to assure proper retention o f all parts.
SUBJECT
D e s c rip tio n ................................................................................................................................................................ 3B1- 1
Diagnosis Of Steering L in kag e ............................................................................................................................. 3B1- 2
On-Vehicle S e r v ic e ................................................................................................................................................. 3B1- 2
Idler Arm Inspection.............................................................................................................................................3B1- 2
Idler Arm Adjustm ent (P30(32) M o to rh o m e )................................................................................................. 3B1- 3
Idler Arm R e p la c e m e n t...................................................................................................................................... 3B1- 3
Relay Rod Replacem ent...................................................................................................................................... 3B1- 5
Pitman Arm R e p la ce m e n t..................................................................................................................................3B1- 6
Steering Shock Absorber In s p e c tio n .............................................................................................................. 3B1 - 7
Steering Shock Absorber Replacem ent.......................................................................................................... 3B1- 8
Tie Rod Replacement (C, G, P20 And 30(42) M o d e ls .................................................................................. 3B1- 8
Tie Rod Replacement (K and P30(00)FS3 M o d e ls ).......................................................................................3B 1- 9
Connecting Rod Replacement (K and P30(00)FS3 M o d e ls)....................................................................... 3B1-11
Connecting Rod Replacement (P30(32) M o to rh o m e ).................................................................................. 3B1-12
S pecifications............................................................................................................................................................3B1 -14
Special T o o ls ............................................................................................................................................................3B1-15
The steering linkage for the C, G, and P20 + 30(42)
model is composed of a pitman arm, idler arm, relay
rod, two adjustable tie rods and a steering shock ab­
sorber (G-model). When the steering wheel is turned,
the gear rotates the pitman arm which forces the relay
rod to one side. The tie rods, which are connected to
the relay rod by ball studs, transfers the steering force
to the wheels. The tie rods are adjustable and are used
for toe-in adjustments. The relay rod is supported by
the pitman arm and idler arm. The idler arm pivots on a
support attached to the frame rail. On the G-model the
steering shock absorber is attached to a relay rod and
a mounting bracket to the steering gear.
The P30(32) Motorhome model steering linkage has
a similar adjustable tie rod assembly as described
above. When the steering wheel is turned, the gear
rotates the pitman arm which forces the nonadjustable
connecting rod and relay arm to move the relay rod to
one side. The relay arm and idler arm are attached to
SECTION 3B1
STEERING LINKAGE
CONTENTS
DESCRIPTION
STEERING LINKAGE 3B1-1
the frame by support assemblies. The support as­
semblies are adjustable for shaft end play. The
steering shock absorber is attached to the frame and
relay arm (figures 1 through 3).
The K model has a front driving axle assembly and
the P30(00) with RPO-FS3 has an I-Beam axle assem­
bly. The steering linkage consists of an adjustable con­
necting rod, steering shock absorber, pitman arm and
a tie rod which connects the two steering knuckles to­
gether (figures 7 and 8).
The overall condition of the steering linkage affects
steering performance. If parts are bent, damaged,
worn or poorly lubricated, improper and possibly dan­
gerous steering action will result.
Whenever any steering linkage components are re­
paired or replaced, check the steering geometry and
front end alignment. Refer to FRONT END ALIGN­
MENT (SEC. 3A).
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