GMC 1989 Light Duty Truck, Repair Manual, Page: 848 / 998

7B1-10 HM-290 MANUAL TRANSMISSION
K H 0 0 2 7 -H M 2 9 0
Figure 15 Removing 2W D Rear Housing
J 3 6 5 1 5-1 2
2 0 3 B E A R I N G , C O U N T E R S H A F T
2 1 2 S H I M , ( S E L E C T I V E )
3 0 0 H O U S I N G , R E A R ( 2 W D )
3 0 2 R E T A I N E R , O U T P U T S H A F T B E A R I N G ( 2 W D )
3 0 4 BOLT, H E X H E A D ( M
8 X 5 0 - 2 2 N m) ( 2 W D )
3 0 5 BOLT, H E X H E A D ( M
8
X 6 0 - 2 2 N m) ( 2 W D )
J 3 6 5 1 5
Figure
16
Re m o ving
2W D
S p e e d S en s o r Rotor
30. Spiral roll Pin (42) using J 36516 (Figure 18).
• Lock up the transmission in 2nd and 4th
gear by sliding the lst-2nd rail assembly
(100) and the 3rd-4th shift fork (108)
downward towards J 36515 (Figure 17).
• Move the black depth locating tang for the
spiral roll pin remover/installer out of the
way, then drive down.
• Put the black depth locating tang back in
place with the rod going through it.
• Turn J 36516 counter clockwise till it stops.
31. Snap ring (43).
32. Threaded thrust ring (inner) (41), ball (40) and
threaded thrust ring (outer) (39).
• Hold the countershaft against the mainshaft
on 2WD models.
• Turn J 36516 clockwise till both threaded
thrust rings (39) and (41) are completely
apart.
33 4WD Rear Housing Assembly (301) and bearing
(203) (Figure 19).
• Tap upwards on the housing with a rubber
hammer (alternately on each side).
• Save the ball bearing outer race (38) that
will be left in the rear housing.
34. Reverse idler gear assembly (46) and countershaft
(53) (Figure 20).
35. 1-2 shift rail assembly (100), 5-Reverse shift rail
assembly (111), 2 and 3-4 shift fork (108).
• By Snapping them off
36. Mainshaft assembly (4) or (5).