GMC 4000 Series Service Manual page 482

Fire Wall Bracket
Retainer and Floor Seal
Screw
Clamp
Steering Column
Lower Column Bearing
Inner Seal
8 Outer Seal
can produce a telescoping effect through steering
gear and column to the steering wheel, and it may
be difficult to determine whether trouble is in
steering column, gear assembly, or linkage com­
ponents. Some of the most common causes of
steering clunk, or chucking movment are as fol­
lows:
a. Insufficient lubricant in steering gear a s­
sembly.
b. Pitman arm loose on Pitman shaft.
c. Steering gear loose on chassis frame.
d. Steering gear incorrectly adjusted.
e. Air pressure in tires too high.
f. Shock absorbers defective.
g. Worn king pins and bushings.
STEERING GEAR ADJUSTMENTS
(Refer to Figure 3)
The steering gear assembly is designed to
provide adjustment to compensate for normal wear
at worm bearings, Pitman shaft, and mating parts.
Before adjustments are made to the steering
gear in an attempt to correct such conditions as
shimmy, loose or hard steering and road shocks,
a careful check should be made of front end align­
ment, shock absorbers, wheel balance, and tire
pressure for possible causes.
NOTE: Before making any steering gear ad­
justment, check lubricant in gear housing and fill
G M C S E R V I C E M A N U A L
9 Stop Clamp
10 Upper Steering Shaft
11 Upper Shaft Yoke
12 Center Universal Joint Assy.
13 Dust Cap Retainer
14 Lower Steering Shaft
15 Spring
16 Spring Seat
Figure 2 — Steering Colum n Stop Clam p Components
to proper level, if necessary, as directed in LU­
BRICATION (SEC. 0) of this manual. Tighten all
mounting bolts to torque recommended in "Speci­
fications" at end of this section.
steering gear must be performed in sequence
given in the following paragraphs:
and adjust if necessary, before making Pitman shaft
lash adjustment.
steering gear, loosen back-up adjuster lock nut
(if used); then loosen back-up adjuster.
MECHANICAL STEERING
16
Procedures for checking and adjusting the
Always check worm bearing adjustment first,
NOTE: Before making any adjustments on the
Figure 3 — A d ju stin g Sector G e a r Lash
Sec. 9A
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