GM 69.5mm Passenger

1. Install center support snap rings and reverse idler shaft. Torque bolts to 14 ft. lbs.

2. Install drive gear on front of mainshaft and engage with countergear to install center support. Install holding fixture J-29768 on end of drive gear shaft and countergear.

3. Install center support onto mainshaft and countergear expanding snap ring until mainshaft bearing groove seats in snap ring. Expand countergear snap ring and continue installing center support until snap ring seats in countergear bearing groove.

4. Engage gears in 1st and 3rd to prevent turning. Install holding fixture J-29678 on end of drive gear shaft and countergear.

5. Install reverse gear on countergear.

6. Install thrust washer on mainshaft with oil groove facing rearward, then install collar, needle bearing and reverse gear on mainshaft.

Figure 8:

7. Install synchronizer assembly so that the higher clutch hub boss is facing forward, Fig. 8.

8. Install locking nut retainer and nut with chamfered side facing toward front of transmission on mainshaft. Torque nut to 94 ft lbs. Lock the nut by bending down retainer.

9. Install thrust washers and reverse idler gear on reverse idler gear shaft. Torque nut to 80 ft. lbs. Check that flange of plate side thrust washer is fitted to stopper on center support.

10. Install blocker ring, needle bearing and fifth gear on mainshaft.

11. Install counter gear, ball bearing, washer and self-locking nut on rear side of countergear. Torque nut to 80 ft lbs. Remove holding fixture. Reposition synchronizers to neutral position.

12. Grease interlock pins and install in center supports.

Figure 9:

13. Place shift forks into position on synchronizer sleeves and install third and fourth shifter shaft from rear of center support through shift forks, Fig. 9.

14. Install 1st and 2nd shifter shaft through rear of center support and first and second shift fork, Fig. 9.

15. Install reverse and fifth-shifter shaft through front of center support and reverse and fifth shift fork, Fig. 9.

16. Install three detent balls and springs in center support. Install gasket and detent plate. Torque bolts to 14 ft. lbs.

17. Install retaining pins in 3rd and 4th, 1st and 2nd and reverse and 5th shift forks into shifter shafts, supporting end of shafts with a bar.

18. Lubricate countergear needle bearing and install in front side of case.

19. Place gasket on transmission case and install center support along with mainshaft, countergear and drive gear.

20. Install large snap ring on drive gear shaft bearing.

21. Install lock ball and thrust washer on mainshaft. Install snap ring.

Figure 10:

22. Check clearance between fifth gear and thrust washer with a feeler gage. Clearance should be between 0.010-0.016 inch on 1981-84 models, or 0.004-0.012 inch on 1985 models. Adjust clearance by replacing selective thrust washer. Refer to Fig. 10 for thickness of available thrust washers.

23. Install snap ring, ball bearing and clip on mainshaft. Then install speedometer drive gear.

24. Install gasket and extension housing onto center support and case. Torque bolts to 27 ft. lbs.

25. Install gasket and shift lever quadrant onto extension housing. Torque bolts to 14 ft. lbs.

26. Install speedometer driven gear. Torque bolt to 14 ft. lbs.

27. Install back-up light switch on extension housing.

28. Install belleville washer with dished side facing toward drive gear bearing. Install drive gear bearing retainer gasket and retainer. Torque bolts to 14 ft lbs. Seal lower three bolts as viewed from front of transmission with sealing compound.

29. Install release bearing and yoke assembly.