GMC 1989 Light Duty Truck, Repair Manual, Page: 931 / 998

BORG WARNER TRANSMISSIONS 7B4-7
DISASSEMBLY AND ASSEMBLY OF SUB-ASSEMBLIES
680
681 682
643. Main Drive Gear
680. Drive Gear Bearing
681. Pilot Bearings
682. Drive Gear Thrust Bearing
B-08485
❖
Figure 16— Main Drive Gear Bearings
MAIN DRIVE GEAR
Disassem ble (Figure 16)
Tool Required:
J 22912-01 Bearing and Gear Puller
1. Thrust bearing and the race (682).
2. Pilot bearings (681).
3. Bearing (680) using J 22912-01 (figure 17).
j j j l
Clean (Figure 16)
All parts in a suitable solvent.
(Do not spin the bearings dry.)
I ?
Inspect (Figure 16)
1. Parts for damage and wear.
2
. Oil the bearings and check for roughness.
*
A ssem ble (Figure 16)
Tool Required:
J 22912-01 Bearing and Gear Puller
1
. Bearing (680), using J 22912-01 (figure 17).
2. Pilot bearings.
J-22912-01
Figure 1 7 — R em oving the Main D rive G ear B earing
• Use chassis grease to hold the bearings in
place.
3. Thrust bearing and the race (682).
MAINSHAFT
❖
D isassem ble (Fig ure 18)
Tool Required:
J 22912-01 Bearing and Gear Puller
1. 4th speed blocker ring (661).
2. 3rd and 4th synchronizer and the 3rd speed gear
(664).
• Press the mainshaft through the synchronizer,
the blocker ring and the gear using J 22912-01
(figure 19).
• Do not let the synchronizer come apart.
Im p o rtan t
• Do not let the mainshaft fall to the floor.
Remove the snap ring and the 2nd speed gear
thrust washer (
666
).
Remove the 2nd speed gear (667) and blocker ring.
Press the mainshaft through the 5th speed driven
gear (679) using J 22912-01 (figure 20).
Im portant
• Do not let the mainshaft fall to the floor.
6
. Mainshaft rear bearing (678).
• It may be necessary to press the mainshaft
through the bearing using J 22912-01 (figure
20
).
Im p o rtan t
9.
• Do not let the mainshaft fall to the floor.
7. Remove the 1st speed gear thrust washer (677).
8
. Pull the retaining pin out and remove the 1st speed
gear (676) (figure 21).
1st and 2nd speed synchronizer sleeve (674) (figure
22
).
• Mark the hub and sleeve alignment for
reassembly.
• Push the hub out of the sleeve while holding
the springs and keys to avoid losing them.
• Do not lose the antirattle ball and spring (669)
(5 speed only).
Im p o rtan t
• Do not remove the hub. The hub and the
mainshaft are machined together as a set.
10. Synchronizers (630 and 662) (figure 22).
• The synchronizer hub and sleeve are a select
fit, do not mix the parts of the two
synchronizers.
• Mark the hub and sleeve alignment for
reassembly.
• Push the hub out of the sleeve while holding
the springs and keys to avoid losing them.