GMC S Series 1994, Repair Manual

Page: 830 / 919

2 3
1. COVER, TRANSMISSION
2. BOLT, ALIGNMENT
3. BOLT
4. SEAL, O -R IN G
5. PLUG, SHIFT RAIL
6. RAIL, SHIFT
7. FORK, 3RD 4TH SHIFT
8. ARM, SELECTOR
9. PLATE, INTERLOCK
10. FORK, 1ST 2ND SHIFT
11. INSERT
12. PLATE, SHIFT FORK
13. PIN, ROLL
3707r5097
Figure 29—Transmission Cover
1. Turn the shift rail (6) until the selector arm (8) is
disengaged from the fork plates (12).
2. Drive the retaining pin (13) out of the selector arm
( 8 ).
3. Remove the shift rail (6), shift forks (7 and 10),
shift fork plates (12), selector arm (8), interlock
plate
(9), and roll pin.
4. Pry the transmission cover to extension housing oil
seal (4) out.
5. Remove the inserts (11) and shift fork plates from
the forks.
• Note the position of inserts and plates for reas­
sembly.
y | Clean
• All metal parts in solvent and air dry.
Inspect
1. Shift forks.
• For damage or bends.
* For worn inserts.
2. Shift rail.
• For damage and bends.
• For worn or damaged plates.
• For smooth fit in the cover.
3. Transmission cover.
• For cracks and warping.
• For smooth shift rail fit.
• Shaft plug for damage or leaks.
❖
Assemble (Figure 29)
• Coat the shift rail and the cover bores lightly with
transmission assembly grease.
1. Install a new shift rail plug (5), if needed.
• Coat the outside of the plug with sealing com­
pound.
2. Fit the inserts (11) and the fork plates (12) into the
shift forks.
3. First and second (largest) shift fork (10).
• Fit the shift rail into the cover rear bore.
• Hold the shift fork in the cover with the fork
offset to the rear.
• Push the shift rail through the fork.
4. Selector arm (8) and the interlock plate (9).
• Hold the selector arm and the interlock plate in
the cover with the widest part of the plate away
from the cover.
• The shift arm retaining pin hole must be away
from the cover and to the rear.
• Push the shift fork through the arm.
5. Third and fourth shift fork (7).
• Hold the shift fork in the cover with fork offset to
the rear.
• The fork plate must be under the first and sec­
ond shift fork plate.
• Push the shift rail through the fork, into the cov­
er front bore.
6. Turn the shift rail until the front fork plate is away
from the cover and parallel to it.
7. Drive a new retaining pin (13) into the selector arm
(8) and the shift rail (6).
• Be sure the arm and shaft pin holes are align­
ed.
• The retaining pin must be flush with the selector
arm.
8. Install a new oil seal (4).
• Coat the seal with transmission oil.
FRONT COUNTERSHAFT
BEARING
4-4
Remove or Disconnect (Figures 1, 2, 30, and
31)
Tools Required:
J 37358-1, -2 Bearing Race Receiver and Case
Support
J 22912-01 Bearing and Gear Puller
J 37359 Countershaft Bearing Remover
J 8092 Universal Driver Handle