Chevrolet 1988 Light Duty Truck Repair Manual page 103

NOTICE: These fa ste n e rs are im p o rta n t a tta c h in g p a rts in th a t th e y c o u ld a ffe c t the p e rfo rm a n c e o f vita l c o m p o ­
n e n ts a n d system s, a n d /o r c o u ld re s u lt in m a jo r re p a ir expense. They m u s t be re p la c e d w ith on e o f the same p a rt
n u m b e r o r w ith an e q u iv a le n t p a rt i f re p la c e m e n t b e c o m e s necessary. Do n o t use a re p la c e m e n t p a rt o f le sse r
q u a lity o r s u b s titu te d e sig n . T orque values m u s t be used as s p e c ifie d d u rin g re a sse m b ly to assure p ro p e r re te n tio n
o f these parts.
SUBJECT
D escrip tion .........................................................................................................................................................................................3 B 2 - 1
Saginaw Model 525 ........................................................................................................................................................................ 3 B 2 - 2
Saginaw Model 535 ........................................................................................................................................................................ 3 B 2 -
S p e c ific a tio n s ..................................................................................................................................................................................3 B 2 -1 0
A d ju s tm e n t.................................................................................................................................................................................... 3 B 2 -1 0
Fastener T o rq u e ...........................................................................................................................................................................3 B 2 -1 0
Special T o o ls .................................................................................................................................................................................... 3B 2-11
The Saginaw steering gear is the recirculating ball nut
and worm type. The worm is located on the lower end of
the steering shaft. The ball nut is mounted on the worm
and the steel balls act as a rolling thread between the
worm and nut to provide a low friction drive between
them.
Teeth on the ball nut engage teeth on the pitman shaft
sector. The teeth on the ball nut are made so that a tighter
fit exists between the ball nut and pitm an shaft sector
teeth when the front wheels are in the straight ahead posi­
tion. The sector teeth are slightly tapered so that a proper
preload may be obtained by moving the pitman shaft end­
ways by means of a preload adjuster screw which extends
through the gear housing side cover. The head of the pre­
load adjuster and a selectively fitted shim fit snugly into a
T-slot in the end of the pitman shaft, so that the screw also
controls the end play of the shaft.
SECTION 3B2
MANUAL STEERING GEAR
CONTENTS
DESCRIPTION
. The model 525 steering gear is used on G
E
~]m ddeTvehicfelC(figure
The model 535 steering gear is used on the CK, S, T
and M model vehicles, (figure 5).
For visual identification the 535 gear has a four bolt
side cover and the 525 gear has three bolts. The larger
(535) gear has a 28.8 mm (1.137-in.) diam eter worm shaft
measured on the O.D. of the worm thread and a 31.7 mm
(1.25-in.) diam eter pitm an shaft. The sm aller (525) gear
has a 26.2 mm (1.034-in.) diam eter w orm shaft and a 28.5
mm (1.125-in.) diam eter pitm an shaft.
3B2-1
PAGE
6
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