Assembly
ASSEMBLE
Installing Countershaft Assembly:
1. Insert countershaft in transmission case through top opening.
Input Shaft Assembly Installation:
2. Insert input shaft in transmission case through top opening.
Removing Output Shaft:
3. Insert output shaft in transmission case. Mate input and output shaft assemblies by positioning them at an upward angle and setting them together.
Installing Center Bearing Race:
4. Install output shaft center bearing outer race, using a suitable drift. Seat center bearing outer races, maintaining bearing position shown in the Center Bearing Race Installation image.
5. Install countershaft center bearing. Ensure center bearing outer races are squarely positioned in bores.
Removing Center Bearing Cover:
6. Install center bearing cover onto transmission case with reference arrow pointing upward. Insert center bearing cover retaining bolts, then torque to 14-19 ft lbs. Ensure all center bearing cover retaining bolt heads are marked with an "8".
7. Position transmission with input shaft and clutch housing facing upward, then install front cover oil seal, using front cover seal installer tool No. T77J-7025-G or equivalent. Ensure input shaft front bearing outer race is squarely positioned in bore.
Measuring Dimensions A, B, C & D:
8. Manually install countershaft front bearing. If any related components have been replaced, measure dimensions A, B, C, and D, then if necessary select a suitable bearing shim that will bring endplay to within limits. Dimensions are as follows:
Installing Selected Shim:
a. Dimension A-height of input shaft bearing outer race above transmission front bearing cover mating surface.
b. Dimension B-depth of front cover outer race bore (input shaft).
c. Dimension C-depth of countershaft front bearing race (transmission case to front cover mating surface).
d. Dimension D-depth of front cover outer race bore (countershaft).
9. Shim computation equations are as follows:
a. Dimension B-(Dimension A + shim thickness) = 0.050-0.150 mm (0.002-0.006 inch).
b. Dimension C + (Dimension D - shim thickness) = 0.150-0.250 mm (0.006-0.010 inch).
Shaft Installation Selective Shim Chart:
c. If necessary to adjust endplay, select a suitable shim from the Shaft Installation Selective Shim Chart.
10. Remove any sealant residue on mating surfaces of transmission and front cover.
CAUTION: To prevent damage to oil seal lip during assembly, tape the input shaft splines along their length.
Countershaft Front Bearing Bore Selective Spacer Chart:
11. Apply a thin coat of oil to front cover (install shim with groove showing). Select a suitable spacer from the Countershaft Front Bearing Bore Selective Spacer Chart, then assemble spacer to transmission case countershaft front bearing bore.
NOTE: If necessary, apply a suitable grease to spacer, bearing cover and oil baffle to retain them during assembly.
12. Apply a 1/8 inch bead of silicone rubber D6AZ-19562-B or equivalent to front cover and front cover retaining bolt threads.
13. Assemble front bearing cover to transmission case, then insert attaching bolts and torque to 9-12 ft lbs.
NOTE: Ensure front bearing cover retaining bolt heads are marked with a "6".
14. Position transmission horizontally in a suitable holding fixture, then install Woodruff key and 5th gear sleeve, using a suitable tool.
15. Install 5th gear needle bearing onto countershaft 5th gear.
Installing 5th Gear:
16. Assemble 5th gear to output shaft, using gear installing spacer tool No. T88T-7025-F, shaft adapter tool No. T75L-7025-P, shaft adapter screw tool No. T75L-7025-K, remover/replacer tube tool No.T75L-7025-A (4x4 models), nut and washer, or equivalents. Ensure long flange on 5th gear faces forward. To install 5th gear assembly on 4x2 models, perform process in two steps; first install gear installing spacer tool No. T88F-7025-F, then when tool bottoms, add gear installing spacer tool No.T88T-7025-G and press 5th gear assembly the rest of the way into position.
17. Place counter lever assembly in transmission, then install thrust washer and retaining ring.
18. Apply a suitable sealant to counter lever retaining bolts, then insert and torque to 6-7 ft lbs.
19. If removed, install 5th-reverse in top cover, then insert 5th/reverse shift rail through top cover bore and 5th/reverse shift fork.
Spring And 5th Gear Installation:
20. Insert spring and detent ball into lower part of shift rod.
5th/Reverse Synchronizer Assembly:
21. Assemble 5th/reverse synchronizer hub, sleeve and 5th gear synchronizer ring to 5th/reverse shift fork and rod assembly.
NOTE: Install longer flange toward front of transmission. Reference mark on synchronizer sleeve must be installed toward reverse side of gear.
22. Assemble 5th/reverse shift fork and shift rail assembly to countershaft, then mate shift fork gate to 5th/reverse counter lever end.
23. Install 5th/reverse shift fork and shift rail assembly with threaded attaching bolt bores aligned.
NOTE: To facilitate assembly, position 5th/reverse shift fork into last of three detent positions. Return shift fork to neutral gear position after installation.
Counter Lever Assembly Installation:
24. Apply suitable sealant to 5th/reverse shift rail attaching bolts, then insert 5th/reverse shift rail attaching bolt into transmission case. Torque bolt to 16-22 ft lbs.
25. Apply suitable sealant to oil passage retaining bolt, then insert oil passage retaining bolt and torque to 6-8 ft lbs.
26. Assemble split washer and thrust washer onto countershaft.
Reverse Idler Gear Endplay Selective Split Washer Chart:
27. If clutch hub and/or counter reverse gear have been replaced, select new split washers from the Reverse Idler Gear Endplay Selective Split Washer Chart that will bring endplay to 0.0O39-0.0078 inch. Ensure split washers are a matched set of identical thickness.
28. Install reverse synchronizer ring and needle bearings into counter reverse gear, then assemble counter reverse gear and needle bearings onto countershaft as an assembly.
29. Install thrust washer onto countershaft.
30. Manually press thrust washer forward against shoulder on countershaft, then while maintaining forward pressure, insert feeler gauge between thrust washer and counter reverse gear and measure endplay.
Counter Reverse Gear Selective Thrust Washer Chart:
31. Counter reverse gear endplay should be 0.007-0.011 inch. If endplay is not as specified, select a suitable thrust washer from the Counter Reverse Gear Selective Thrust Washer Chart that will bring endplay to within specifications.
32. Temporarily install a suitable spacer in place of countershaft bearing, then loosely install countershaft locknut to retain components. Installation of a suitable spacer prevents thrust and split washers from slipping off shaft and avoids interference with reverse idler gears.
33. Install reverse idler gear assembly, then apply a suitable sealant to attaching bolt.
34. Insert reverse idler gear attaching bolt, then torque to 58-86 ft lbs.
35. Drive sleeve and reverse gear assembly onto output shaft using a suitable tool. Ensure longer flange of reverse gear is facing rearward.
36. Install output shaft rear bearing using a suitable tool.
37. Remove temporary spacer from countershaft.
38. Manually install countershaft rear bearing.
CAUTION: Torquing shaft locknuts without fully seating can cause damage to output shaft threads.
39. Lock transmission in 1st and 3rd gears, then install and finger tighten new output and countershaft locknuts.
40. Torque output shaft locknut to 160-200 ft lbs, then torque the countershaft locknut to 94-144 ft lbs.
NOTE: New locknuts must be used.
41. Stake locknuts to bottom shaft groove using a suitable tool, then install speedometer drive gear and steel ball into output shaft.
42. On 4x2 models, install speedometer drive gear to output shaft retaining ring.
NOTE: Speedometer drive gear contains three detents into which steel drive ball can be installed into either detent. Depending on application, one of two different speedometer drive gears may be installed. Replace gear with same color as was removed.
43. Remove any sealant residue from mating surfaces of transmission case and extension housing, then apply a 1/8 inch bead of suitable sealant to transmission case. Extension housing bushing cannot be serviced. If bushing requires service, extension housing must be replaced as a unit.
44. Position extension housing on transmission case, then insert attaching bolts and torque to 24-34 ft lbs.
45. Place synchronizers in neutral, then ensure shift forks on top cover assembly are in neutral position.
46. Place top cover on transmission case, then engage shift forks with synchronizers.
47. Apply a suitable sealant to the two rearmost cover retaining bolts, then insert and finger tighten the bolts. Insert retaining top cover retaining bolts, less sealant, then torque all bolts to 12-16 ft lbs.
NOTE: Do not apply sealant to top cover or transmission case mating surfaces.
48. Install transmission drain plug and torque to 29-43 ft lbs.
49. If removed, install rear extension housing oil seal using a suitable tool. Ensure oil seal drain hole is facing downward.
50. Fill transmission with specified quantity of fluid.