Disassembly of Automatic Gearbox

Gearcase And Torque Converter Housing

Important: It is very important to observe great cleanliness when working on the gearbox. Dirt particles can seriously damage the function and service life of the gearbox.





1. Drain the oil from the gearbox before removing any parts. Remove the gearbox from the car.
Fit the dipstick pipe.
2. Plug the shaft hole. Clean the exterior of the gearcase. Use plug 91 32 929, and seals 91 32 937 and 87 92 244. Plug the breather pipe.
3. Undo the connectors and remove the wiring harness.
4. Remove the dipstick pipe. Remove the selector lever bracket.





5. Fit holder 87 92 392 to the gearbox with an M8x25 flange bolt.
Position the gearbox on stand 78 74 878.

Note: During removal it is important that the work area is well organized with groups of associated parts to facilitate fitting.





6. If there is an engine mounting on the gearbox, remove it.





7. Pry out the lock washer on the nut of the gear selector position sensor, and loosen the nut slightly.
8. Remove the gear selector position sensor. (NOTE different cable lengths.)





9. Unplug the connectors to the speed sensors and temperature sensor.
Remove the speed sensors.





10. Fit tool 87 92 681 or 87 91 766 to the torque converter. Remove holder 87 92 277 or 87 92 574. Remove the torque converter.





11. Turn the gearbox 180° on the stand.





12. Remove the cover plate and temperature sensor.
13. Remove metal cover of the torque converter housing.





14. Remove the bolts holding the valve housing cover and tap off the cover using a shatterproof plastic mallet.

Important Take care that the sealing surfaces are not damaged.





15. Disconnect the electrical connectors of the solenoids. Lift the casing of the system pressure solenoid slightly with a small screwdriver to release the catch. Unhook the cable. Pull the cable and grommet out of the gearcase. Place the holder to one side.
16. Remove the bolts of the valve housing (only bolts with 10 mm head). Keep the small cover safe.
17. Unhook the piston rod of the manual valve from the valve control and remove the valve housing.





18. Remove the two seals.
19. Remove the bolts securing the oil pump to the gearcase.





20. Pull the oil pump and brake unit B2 off from the gearcase using puller 87 92 699.





21. Remove the brake hub and freewheel F1.





22. Turn the gearbox 90° on the stand.





23. Remove the torque converter housing. Knock the housing loose using a plastic mallet. Remove the small seal.





24. Lift out the differential unit.
25. Remove the oil strainer and cover panel.
26. Remove the oil duct plate from the gearcase.





27. Remove the twist spring and handbrake pawl pin.
28. Remove the handbrake lever and the gear selector position plate. Detension the catch spring.
29. Remove the pin seal from the selector lever pin.





30. Remove the handbrake lever bracket and the catch spring.





31. Remove the handbrake pawl and guide pin.
32. Remove the bracket and twist spring.





33. Remove the cover with O-ring, piston and spring.
34. Lift out the output shaft complete with thrust bearings and bearing races.





35. Lift out clutch C3 and the bearing race. Keep the thrust bearing safe.
36. Lift the brake band of brake B4 out of the gearcase.





37. Remove the circlip for freewheel F3 from the gearcase. Lift out F3. Keep the small retainer safe.





38. Remove the oil sealing rings by pressing one side of the ring against the groove and removing the ring.





39. Turn the gearbox 180°





40. Remove the circlip, cover, piston, spring and the two O-rings of the B4 brake piston.

NOTE: take care, the spring can cause the cover and piston to fly off.





41. Remove the bolts holding the end cover. Tap off the cover using a plastic mallet. Remove the four seals.





42. Remove the pipe of the C3 solenoid. Use sliding hammer 83 90 270 and hook 87 92 384.
43. Remove the Pipe bracket and remove the other pipe. Use sliding hammer 83 90 270 and hook 87 92 384.
44. Remove the bearing and bearing race from the cover and the bearing race from the turbine shaft unit with clutch C1 and C2.





45. Lift out the turbine shaft unit with clutch C1 and C2. Keep the thrust bearing and thrust bearing race safe.
46. Lift out sun gear of the planetary gear set and the thrust bearing. Keep the thrust bearing race safe.





47. Remove the rear ring gear. Keep the thrust bearing and bearing race safe.
48. Lift out the planetary gear set and the large thrust bearing.





49. Remove the circlip from freewheel F2 and brake B3 with a screwdriver. Lift out the ring gear with F2 and B3 which contains a plate assembly and flanges.
50. Keep the thrust bearing and bearing race safe.
51. Remove the circlip from the spring package using a screwdriver. Lift out the spring package.





52. If necessary, remove the accumulator of C1 from the end cover with spring and piston.
53. Remove the plug by the end cover





54. Carefully apply compressed air at a pressure of 4 bar through the oil duct for B3 (as illustrated) to remove the B3 piston. If the piston does not come out, assist removal with needle-nose pliers.





55. Turn the gearbox 90°.
56. Remove the circlip of the idler. Use circlip pliers 87 90 180 with tips 87 90 297 and a small screwdriver. Remove the idler.
57. Turn the gearbox 90°





58. Remove the drive shaft seal using a hammer and screwdriver.





59. Fit pullers 87 92 707 and 87 92 715. Remove the bearing race from the gearcase by heating the gear case with a heat gun for about 5 minutes. Pull out the bearing race and keep the shims safe.





60. Remove the brake band holder and the remaining plugs from the gearcase. (Do not mix up the plugs.)





61. Remove the bolt and pipe clip from the torque converter housing.
62. Detach both ends of the pipe using sliding hammer 83 90 270 and hook 87 92 384. Remove the pipe. Be careful not to damage the pipe.
63. Remove the oil duct plate, (three bolts). Remove the three magnets.





64. Fit pullers 87 91 675 and 87 91 683. Heat the bearing seat for about 5 minutes with a heat gun and remove the roller bearing.
65. Tap out the shaft seal.





66. Remove the bearing race of the conical roller bearing in the torque converter housing by heating around the bearing seat with a heat gun for about 5 minutes. Pull out the bearing using pullers 87 92 707 and 87 92 715. Remove the washer (certain variants only). The bearing need only be removed if the torque converter housing or differential bearing is changed.