GMC 1989 Light Duty Truck, Repair Manual, Page: 920 / 998

7B3-8 NEW PROCESS TRANSMISSION
418
407
414
407. 3rd and Overdrive Synchronizer
409. Overdrive Gear
410. 2nd Speed Gear
412. 1st and 2nd Synchronizer (Reverse Gear)
414. 1st Speed Gear
416. Extension Housing
418. Main Shaft
B-08864
Figure 10— Mainshaft Assembled
• Install the gear with the cone into the blocker
ring.
5. Press the rear bearing (415) on and install a new
snap ring.
Im portant
Use the correct snap ring, it is a select fit to
limit the mainshaft end play.
6
. Install the speedometer drive gear (420) and the
retaining clip.
7. Overdrive gear (409) and the blocker ring.
• Slide the gear on with the cone to the front.
• Slide the blocker ring onto the gear cone with
the clutching teeth to the rear.
8
. Install the 3rd and overdrive synchronizer (407) and
a new snap ring.
• The shift fork slot must be to the rear.
• The hub slots must be engaged with the
blocker ring.
9. Install the 3rd speed blocker ring with the clutching
teeth to the front.
• The ring must be engaged with the
synchronizer hub slots.
• Hold the ring in place with grease.
427 428 476
476 430
428
427. Thrust Washer 431. Countershaft Spacer
428. Countershaft
476. Bearing Spacers
Bearings
430. Counter Gear B-08868
❖
i j j i
13
*
Figure 11— Countergear and Components
COUNTERGEAR
D isassem ble (Figure 11)
Tool Required:
J 29793 Countershaft Alignment Tool
Remove tool J 29793.
Remove the bearings (428) and the spacers.
1
.
2
.
3. Remove the countershaft spacer (431).
Clean
All parts in suitable solvent and air dry.
Inspect
Countergear for nicks, burrs, and broken teeth.
Bearings for wear and rough surfaces.
Spacers for wear and grooves.
Countershaft for wear, nicks and burrs.
M easure
• C ountershaft to case bore clearance.
Clearance must be no more than 0.127 mm
(0.005-in.).
A ssem ble (Figure 11)
Tool Required:
J 29793 Countershaft Alignment Tool
• Coat the inside of the countergear with grease.
1. Install the countershaft spacer (431) using J 29793.
2. Install the bearings (428) and the spacers.
• Be sure the bearings and the spacers are
centered.
3. Install a thrust washer (427) to the front of the
countergear with the tab inside the countergear.
EXTENSION HOUSING
R em ove or D isconnect (Figure 12)
Tools Required:
J 23062-14 Extension Housing Bushing
Remover
J 8092 Driver Handle
1. Seal (421).
2
. Gasket material from flange of the extension (416).
3. Bushing (478) if it is worn or damaged, using
J 23062-14.