Steps 1 Through 50

Assembly Of Automatic Gearbox





1. If the torque converter housing is changed, transfer the outer plugs to the new housing. Carefully remove any old sealant from the sealing surfaces using a gasket scraper, and wash the torque converter housing.





2. Heat the bearing seat with a heat gun and tap the roller bearing into the torque converter housing using drift 87 90 461 and handle 83 90 189.
Press in the bearing with the text facing downwards until it reaches the bottom of the torque converter housing. The side of the roller bearing forms the bearing race of the output shaft's thrust bearing.





3. Heat the bearing seat of the differential bearing race in the torque converter housing. Fit a washer on the variants that require this and fit the bearing race. Check that the bearing race is in contact with the bottom by trying to turn the washer. The washer should not turn.





4. Place the three cleaned magnets on the oil reservoir plate. Apply threadlock 74 96 268 to the bolts and fit the oil duct plate.
Tightening torque 5.5 Nm (4 ft. lbs.)
5. Fit the pipe using a plastic mallet. Be careful not to bend or damage the pipe. Fit the pipe clip.





6. Heat the bearing seat of the differential bearing race in the gearcase for about 5 minutes. Refit the shims and fit the bearing race. Check that the bearing race is in contact with the bottom.





7. Grease the bearings with transmission fluid. Fit the differential and fit the torque converter housing. Only fit every other bolt. Fit a dynamometer 87 92 483 and drift 87 91 337 to the differential housing. Turn until the reading is stable.
Tightening torque 24 Nm (18 ft. lbs.)
Measure the preload. Start value:
New bearing 1.0 Nm (7 ft. lbs.)
Refitted bearing 0.5 Nm (3.5 ft. lbs.)





8. If the preload deviates from the specified value, remove the differential and bearing race from the gearcase and change the shims.
If the reading exceeds the value above, thinner shims should be used.
If the reading is lower than the given value, thicker shims should be used. Shims are available in varying thicknesses from 1.0 - 1.90 mm
9. Remove the torque converter housing and lift out the differential.
10. Turn the gearbox 90°.





11. Fit new O-rings to the B4 brake piston and the piston cover. Grease the servo piston with Vaseline and fit the piston and cover. Fit the circlip.
12. Turn the gearbox back 90°





13. Bend out the rings and position them in the grooves. Do not stretch them more than necessary.
14. Grease the two oil sealing rings of clutch C3 with Vaseline.





15. Grease new flawless O-rings with Vaseline and fit them to the accumulator piston and the cover. Fit the spring and piston. Fit the cover and bracket with twist spring. Press down the bracket and tighten the bolts.
Tightening torque 10 Nm (7 1bf ft)

Important: Do not press the accumulator cap further down than the holder allows. The O-ring can be damaged on sharp internal edges.





16. Fit the freewheel F3 to the bottom of the gearcase and fit the retainer. (NOTE its location)

17. Fit the circlip with a screwdriver. Make sure that the opening of the circlip is not aligned with any of the recesses in the groove.





18. Grease the O-ring on the anchor bolt with Vaseline and tighten it.
Tightening torque 140 Nm (104 ft. lbs.)
19. Fit the brake band and the anchor bolt pin in the brake band recess.





20. Fit the thrust bearing greased with Vaseline. Fit the black section against the gearcase.
21. Fit clutch C3 into the gearcase. Lift the brake band slightly to facilitate fitting. Make sure that the clutch runs freely anticlockwise and locks clockwise.
22. Align the teeth of clutch C3 using a small screwdriver.
23. Fit the bearing race to the sun gear and the thrust bearing to the planetary gear set. Fit the output shaft complete with clutch unit C3. Make sure that the shaft assumes the correct position in the hole for the large gear. Check that the shaft and gears rotate freely.
24. Fit the thrust bearing race and thrust bearing to the output shaft unit.





25. Position the pawl on the correct side of the spring.
26. Fit the guide pin in the hole. Position the guide fork, pawl pin and spring.





27. Fit the selector lever position spring of the ratchet. (NOTE different length bolts.)
Tightening torque 5.5 Nm (4 ft. lbs.)





28. Press in a new oil seal greased with Vaseline into the selector lever pin. Apply Vaseline to the lips of the oil seal.
29. Fit the lever and ratchet together (detension the spring). Make sure the handbrake pawl assumes its correct position and works. Move the selector lever to neutral.
30. Fit the oil duct plate to the gearcase (short bolts). Tighten the bolts.
Tightening torque 5.5 Nm (4 ft. lbs.)
31. Fit the cover with two bolts.
Tightening torque 5.5 Nm (4 ft. lbs.)
32. Fit a new oil strainer and tighten the bolts. Make sure the seals are correctly positioned, one on each side.
Tightening torque 5.5 Nm (4 ft. lbs.)
33. Fit the differential housing unit.

Important: Check the differential housing internally for damage. Also check the drive shaft surfaces.

34. Clean the sealing surfaces of the gearcase and torque converter housing. Use cleaner 30 02 599. Keep the surfaces free of grease and oil.
35. Fit a new seal in the gearcase.





36. Apply a 1 mm thick bead of flange sealant 87 81 841 to the gearcase as illustrated and fit the torque converter housing.





37. Apply thread sealant 74 96 284 to the internal bolts. Fit the bolts (different lengths). Tighten the bolts.
Tightening torque 25 Nm (18 ft. lbs.)





38. Clean the magnetic surface of the drain plug and fit it with a new washer.
Tightening torque 40 Nm (30 ft. lbs.)





39. Fit the idler assembly into the gearcase.
40. Turn the gearbox 90° in the vertical plane.





41. Use circlip pliers 87 90 180 with tips 87 90 297 to fit the circlip. Press the circlip into the groove with the pliers.
42. Turn the gearbox 90°.





43. Grease two new O-rings for brake B3 with Vaseline and fit them onto the brake piston. Take care not to damage the C-rings. Press the piston into the gearcase.
44. Fit the return spring to the piston and fit the circlip into the groove on the gearcase. Make sure that the circlip opening is not aligned with the large recess. Use a screwdriver and check that the entire ring is seated in the groove.





45. Fit the bearing race and the thrust bearing onto the idler hub.
46. Fit the front ring gear and freewheel F3. Check that the thrust bearing is correctly positioned and that the ring gear rotates freely anticlockwise and locks clockwise.





47. Fit the flanges and plate assembly as illustrated.

Important: The large recess in the flanges and plates must be aligned in front of the brake bands to B4. Make sure that they are fitted in the correct order.





48. Fit the circlip to the gearcase. Check that the circlip opening is not aligned with the recess.
49. Connect a compressed air supply at a pressure of 4 bar to the oil duct as illustrated. Check that the piston moves freely.





50. Grease the thrust bearing for the planetary gear set with Vaseline and fit the bearing to the front ring gear. Check that the black side is facing upwards.