Changed Flex Discs-Bearing-Transmission Parts
Here are my notes for some spring work on the C230.
1997 C230 with 244,000 milesAll parts came from Autohausaz and German Imports, unless designated.
C230 Repair Steps1. Disconnect O2 Sensor in engine compartment and cover end with plastic bag to prevent contamination.
2. Spray front exhaust bolts from manifold to pipe with penetrating oil.
3. Raise vehicle, and place on ramps. (I used four 8 inch Race Ramp foam ramps. They are fantastic-purchased from Amazon).
4. Remove center exhaust bolts and carefully drop rear exhaust by pulling rear exhaust forward until the three exhaust points are clear of the rubber supports. Be careful, the exhaust will drop to the ground.
5. Bring down front O2 Sensor, and tie off.
6. Disconnect second O2 sensor, cover with plastic, and tie off.
7. Remove front exhaust bolts with 13mm socket and extension.
8. Prop up support for front exhaust and remove the two mid support nuts with 13mm socket, thereby carefully lowering to the ground.
9. Remove heat shields with an 8mm deep socket. Use plenty of pressure so as not to round the nuts heads.
10. Inspect the drive line.
11. Support the transmission with a scissors jack and a block of wood, just forward of the torque convertor. Put enough pressure to just press upward.
12. Loosen and remove the two 16mm bolts that run from the transmission support in to the back of the transmission.
13. Loosen and remove the four 17mm bolts that hold the plate under the transmission support, and remove the plate and the support as one unit.
14. Remove the two tunnel cross members, each unit has two 13mm bolts.
15. Mark the drive line position as to how each section aligns to the next: rear, middle, front
16. Examine the front flex disc as to how it is positioned to the flange and the front propeller shaft.
17. Loosen the front flex disc and remove the three bolts that hold the flex disc to the transmission flange. The bolts are 15mm and the nuts are 17mm, make sure to use only 6 sided sockets or you will strip the nuts.
18. With the flange bolts removed from the flex disc, pull the front propeller shaft backwards so that the flex disc clears the transmission shaft and drops downwards. As soon as the flex disc is cleared of the transmission, then pull the propeller shaft forward and it will release from the splines on the front of the rear propeller shaft, which should still be mounted in the center bearing support.
19. Loosen the rear flex disc and remove the three bolts that hold the flex disc to the transmission flange. The bolts are 15mm and the nuts are 17mm, make sure to use only 6 sided sockets or you will strip the nuts.
20. Remove the center bearing support by loosening the two 13mm bolts, and carefully lowering the center support and the rear propeller shaft to the ground, and then pulling the rear propeller shaft from the differential shaft.
21. At the workbench, take the rear propeller shaft and pull the center mount support from the bearing, and discard. You might need to use a puller to separate the center mount support from the bearing.
22. Use a puller to pull the bearing.
23. Clean the bearing shaft and lubricate lightly. Replace the bearing by tapping in place using a piece of 1inch ID plastic pipe and tapping lightly with a hammer. Drive it in place until well seated.
24. Slide the new bearing support mount in place and make sure that it is seated tightly on the new bearing.
25. Look carefully at the alignment of the orientation of the flex disc on the rear propeller shaft. Remove the old flex disc and attach the new flex disc.
26. Slide the rear propeller shaft with the new flex disc and the new bearing, on to the differential shaft and align the new flex disc to the differential flange. Install and tighten the new bolts from the rear flex disc to the differential.
27. Raise the front of the rear propeller shaft in to the tunnel and attach the center mount with the 13mm bolts. Do not yet tighten the 13mm bolts.
28. Return to the workbench and remove the old flex disc from the front propeller shaft, and attach the new flex disc. Leave the front propeller shaft at the workbench.
29. Disconnect the shifting grommet clip, and separate the shifting linkage. Remove the old grommet and insert the new grommet, then install a new clip. (purchase the grommet tool from Samstag Tools)
30. Put catch basins in place and drain the transmission fluid from the transmission and the torque convertor. (You might need to tap the key several times to bring the torque convertor drain in place.)
31. At the passenger front of the transmission pan, remove the lower 30T screw and slide out the cover plate, which will then reveal the transmission electric connection.
32. Slide the outer ring of the connection counter clockwise and the connection will come out of the socket.
33. Carefully pull the connector out of the socket and do not be surprised if there is transmission fluid dripping all over. Wipe of the connector and tuck it out of the way.
34. Reach in to the center of the socket with a 7mm extended socket and unscrew the socket, then pull it out of the transmission. Make sure to account for both of the o-rings. Carefully orientate the new socket in the transmission hold, and make sure to get it seated all the way in the hole. Then tighten with the 7mm socket. Place the connector in the socket and rotate the collar clockwise to seat the connector. Do not put the cover plate in place at this time.
35. At the back of the transmission shaft, use a 30mm 12 point thin walled socket to remove the rear nut that is holding the flange in place.
36. With the transmission nut removed, then pull the flange off of the shaft.
37. The rear transmission seal will now be exposed, and use a seal puller to gently pull the seal from the transmission. Take the new seal and place it in position, pressing it in with your fingers. Then tap it in with rubber mallet until flush with the transmission. Slide the flange back in place and attach with a new nut. Make sure to strike the nut to prevent it from turning loose.
38. Remove the six 30T bolts from the transmission pan, and drop the pan.
39. At the workbench, carefully clean the pan from all foreign debris and install the new pan gasket.
40. Under the transmission, turn the parking interlock cable counter clockwise to disengage the parking interlock cable from the fitting.
41. Remove the 30T screw from the cable fitting located in the transmission.
42. Under the transmission, strike the pawl pin and loosen the pin outward.
43. Disconnect the pawl from the end of the fitting and pull out the old fitting.
44. Insert the new fitting and attach to the end of the pawl, then insert the pin back through the pawl and the torsion spring, making sure to align the spring, the pawl, and the fitting.
45. Attach the interlock cable to the fitting by inserting the cable in to the fitting and turning the cable clockwise to lock.
46. Retrieve the transmission pan and attach to the bottom to the transmission, carefully cross tightening. Then replace the drain plug in the torque convertor and the transmission pan. You can also reattach the cover for the electrical connector.
47. Retrieve the front propeller shaft and align the splines with the rear propeller shaft and slide them together at the center support; then pull the propeller shaft forward over the transmission shaft and align the flange with the flex disc. Install the bolts between the flex disc and the transmission flange.
48. Align the center support and tighten.
49. Reattach the two tunnel cross supports.
50. Reinstall the transmission mount and release the scissors jack.
51. Reinstall the heat shields.
52. Replace all three muffler rubber supports.
53. Install rear exhaust pipe.
54. Install front exhaust pipe.
55. Attach O2 sensors.
56. Lower vehicle to ground.
57. Add transmission fluid
58. Drive and enjoy your work!