Part 3
TRANSFER CASE OVERHAUL - Part 3NOTE: Before commencing the overhaul procedure thoroughly clean the exterior of the transfer case. If the gearbox oil has not previously been drained, drain the oil into a suitable container.
Rear Output Housing, Dismantle And Inspection
1. Support the rear output housing by the output shaft in a vice fitted with soft jaws.
2. Using service tool 18G1205 to hold the drive flange, release and remove the Nyloc nut and plain washer securing the drive flange to the output shaft. Withdraw the rubber seal. Discard the nut and seal.
3. Remove the drive flange from the output shaft. Examine the flange for damage or wear particularly the seal running surface. If the surface is corroded or a groove has been worn by the previous seal discard the flange.
4. Pry the speedometer sleeve and driven gear from the housing. Examine the gear teeth for wear, if worn discard the gear.
5. Pry the oil seal from the sleeve and remove the O-ring. Discard both the seal and O-ring.
6. Clean the sleeve and place to one side.
7. Drive or press the output shaft from the housing.
8. Clean and examine the splines and speedometer drive gear for wear or damage. The output shaft can he further dismantled if either the speedometer drive gear or output shaft is worn as follows: remove the circlip and slide the gear from the shaft, retrieve the ball bearing from the indent in the shaft. Discard the worn component.
NOTE: While the output shaft is removed from the rear output housing, the shaft can be utilized for checking the rolling resistance of the viscous unit as follows.
Viscous Unit Rolling Resistance, Bench Check
NOTE: Testing should be carried out in an ambient of 68 °F (20 °C).
9. Secure the output shaft in a vice fitted with soft jaws, gripping the shaft on the drive flange splines.
10. With the viscous unit still installed in the front output housing place the assembly on the rear output shaft spline.
11. Apply a torque of 27 Nm (20lb ft) to the output flange nut, if no resistance to turn is felt, the viscous unit requires replacing.
12. If resistance to turn is felt, apply a torque of 27 Nm (20 lb ft) to the output flange nut for 1 minute. This should result in a rotation of approximately 25°-30°. If this does not occur, the unit requires replacing.
13. Lever off the dust shield.
14. Pry the oil seal from the housing and discard the seal.
15. Remove the circlip retaining the bearing.
16. Drive or press the bearing from the housing. Discard the bearing.
17. Remove any previous sealant from the housing joint face.
18. Thoroughly clean all components with a suitable solvent.
19. Examine the housing for damage and wear. Renew as necessary.
Rear Output Housing, Assemble
20. Drive or press a new bearing into the housing until the bearing contacts the shoulder.
21. Fit the circlip.
22. Lubricate a new oil seal. Using oil seal replacer 18G1422 fit the seal, lip side forward until it contacts the circlip.
23. Fit the dust shield.
24. Place the ball bearing in the indent on the output shaft, fit the speedometer drive gear to the shaft, secure together with the circlip.
25. Press or drive the output shaft into the housing until the shoulder of the shaft contacts the bearing.
26. Lubricate the oil seal bearing surface of the drive flange and fit the flange followed by a new rubber seal. Fit the steel washer and secure the flange to the shaft using a new nut. Tighten to 203-244 Nm (150-180 ft lb).
27. Lubricate a new speedometer sleeve oil seal, and press the seal into the top of the sleeve.
28. Fit a new O-ring to the outside of the sleeve, push the driven gear spindle into the sleeve.
29. Lubricate the O-ring and push the sleeve and gear assembly into the housing. it may be necessary to rotate the output shaft to ensure that the driven gear engages with the drive gear on the shaft.
30. Apply Dow Corning 732 or a suitable equivalent silicone sealant to the rear output housing joint face on the main casing. Evenly spread the sealant on the face to ensure a good seal.
31. Fit the housing to the main casing and secure with the six bolts tightened to 30-49 Nm (22-36 ft lb).
Front Output Housing, Dismantle And Inspection
1. Support the viscous unit and front output housing in a vice fitted with soft jaws gripping on the two flats of the viscous unit.
2. Using service tool 18G1205 to hold the drive flange, release and remove the Nyloc nut and plain washer securing the drive flange to the output shaft, withdraw the rubber seal. Discard the nut and seal.
3. Remove the drive flange from the viscous unit. Examine the flange for damage or wear particularly the seal running surface. If the surface is corroded or a groove has been worn by the previous seal discard the flange.
4. If necessary the oil catcher can be carefully pressed from the drive flange, if either a new oil catcher or bolts are being fitted.
5. Carefully tap the viscous unit out of the housing. If the original unit is being refitted wipe clean with a clean cloth.
NOTE: The viscous unit is a sealed assembly and cannot be further dismantled. A new unit should be fitted if the unit is damaged or if the turning torque is out of limits.
6. Pry the oil seal out from the front output housing and discard.
7. Remove the circlip retaining the bearing.
8. Drive or press the bearing from the housing and discard.
9. Clean the housing with a suitable solvent.
10. Remove any previous sealant from the joint face of the housing.
11. Examine the housing for damage and wear, renew the housing if necessary.
Front Output Housing, Assemble
12. Drive or press a new bearing into the housing
13. Fit the circlip to retain the bearing.
14. Lubricate a new oil seal. Using oil seal replacing tool 18C1422 fit the seal, lip side of the seal forward until it contacts the circlip.
15. Carefully tap the original or new viscous unit into the housing until contact is made with the face of the bearing.
16. Lubricate the lips of the seal and fit the flange followed by a new rubber seal. Fit the steel washer and secure the flange with a new nut. Tighten to 203-244 Nm (150-180 ft lb).
17. Apply Dow Corning 732 or a suitable equivalent silicone sealant to the output housing joint face of the main casing. Evenly spread the sealant on the face to ensure a good seal.
18. Fit the housing to the main casing and secure in position with the eight bolts tightened evenly to 24-31 Nm (18-23 ft lb).
19. Refit the gearbox to the vehicle.