GMC 1989 Light Duty Truck, Repair Manual, Page: 182 / 998

4B4-6
10
1/2-INCH RING GEAR
2. O u te r pinion b e a rin g cup (6) using J 8 6 0 8 and
J 8 0 9 2 .
3. in n er pinion b earing cup (13) using J 2 4 4 3 2 and
J 8 0 9 2 .
4. A new co llapsible sp ac er (12) to the pinion.
5. Pinion (14) into the pinion g ag e (10).
6
. Pinion o uter b earing (6) onto th e pinion.
• Press th e b earing onto th e pinion.
7. Pinion oil seal (5) using J 2 4 4 3 4 and J 8 0 9 2 .
8
. Pinion flan g e oil d eflecto r (4) and pinion flan ge (3) to
th e pinion splines.
9. W a s h e r (2) and a new pinion nut (1).
• P lac e th e pinion c a g e assem b ly into the vice.
10. F la n g e h older J 8614-01 to th e pinion flange.
T ig h te n (F igure 11)
• T h e nut until th e pinion end play is just taken
up. R otate th e pinion w hile tightening in order
to se at th e bearings. O n c e th ere is no end play
in th e pinion, th e preload torque should be
ch ecked.
• R e m o v e J 8 6 1 4 -0 1 . U s in g an in c h -p o u n d
torque w ren c h , ch ec k th e pinion preload by
rotating th e pinion with th e w rench. Preload
should be at or below 2.8 to 4.0 N m (25 to 35
in. lbs.) for new b earing s, or 0.56 to 1.7 N-m
(5-15 in. lbs.) for used b earin g s (figure 12).
• If th e preload torque is below the preloads
given above, co n tin u e torquing th e nut in sm all
inc re m en ts. C h e c k th e p relo ad afte r ea ch
tig h te n in g . E a c h tig h te n in g in c re a s e s th e
b e a rin g p relo ad by several pounds. If th e
b earing preload is ex c e e d e d , the pinion will
have to be rem o ved, and a new collapsible
s p a c e r installed.
• O n c e th e preload has been o b tain ed , rotate
th e pinion several tim es to assu re that the
bearing s have se ate d . R e c h e c k th e preload,
and adjust if necessary.
11. P inion c a g e (10) to th e a x le h ou sin g. R e fe r to
“ Pinion Installatio n ” in this section.
PINION INSTALLATION
I+ + I Install or C onnect
Tools Required:
J
34943 Pinion Pilot Bearing Installer
J
8092 Driver Handle
1. Pinion pilot bearing (15) using
J
34943 and
J
8092
(figure 13).
• Bolt the guide plate to the axle housing.
• Place the bearing (15) onto the guide.
• Drive the bearing into the housing. The part
number of the bearing must face the pinion
flange.
• Measure the pinion bearing shims (11). If a new
pinion and ring gear set is installed, the pinion
bearing shim pack must be adjusted.
• Examine the heads of the new and old drive pinions.
C om pa re th e s e codes, and a d ju s t th e p in ion
bearing shim pack accordingly. The chart in figure
14, shows the proper adjustm ent to be made to the
shim pack.
• Pinion service shims are available in sizes from
0.006 to 0.024-inch.
• If the original pinion is being used, the original
pinion shims should also be used.
2. Pinion bearing shims (11) to the pinion cage.
• The shims, housing, and cage must be clean.
3. The pinion cage (10) to the axle housing (figure 15).
4. Cage bolts (7).
& T ig h te n
• T h e bolts to 88 N-m (65 ft. lbs.)
DIFFERENTIAL CASE ASSEMBLY
Install o r C on n e ct (F igure 1)
+«-
Tools R equired:
J 2 4 4 2 9 S id e B earing A d ju s tm en t S p a n n e r
J 8 0 9 2 Driver H a n d le
J 8107 S ide Bearing P uller Plug
Lubricate all parts with rear axle lubricant.
Differential pinion gears (32 ) and thrust w ashers (31)
to the spider (33).