Removing and Installing

Remove and Installing Transmission (S6S 420G SMG)


Special Tools Required:
- 00 2 030
- 23 0 041
- 23 0 042
- 23 0 240
- 00 2 030
- 23 0 041
- 23 0 042
- 23 0 240

Important!
After completing work:
- Proceed according to test program, refer to "Service Functions: in DIS Tester.
- Check transmisison oil level.
Use only the approved transmission oil.
- Check fluid level in hydraulic system.
- Read out fault memory and clear fault entries.
Failure to comply with this requirement will result in serious damage to the transmission.

Necessary Preliminary Tasks:
- Disconnect battery, battery positive lead from battery terminal.
- Remove intake air manifold.
- Remove heater bulkhead.
- Remove fan with fan impeller.
- Remove engine splash guard.
- Remove reinforcement plate.
Important notes on installation are described in this work step.
- Remove exhaust catalytic converter and intermediate pipes.






Remove heat shield (1).






Remove heat shield (1).

Remove bracket for underbody protection at rear.






Disconnect cable plugs for transmission fluid temperature sensor (1) and transmission speed sensor (2).






Disconnect cable plug for reversing light switch (1).






Unclip hydraulic lines at holders (1).

Installation:
- Replace holders (1).






Unclip hydraulic lines at holders (2).

Installation:
- Replace holders (2).

Release nuts and remove clutch slave cylinder (3).






Tightening Torque, 21 52 5AZ.


Important!
Pressure pipe remains connected.
Slowly relieve tension on clutch slave cylinder (3) when removing otherwise air will be drawn in through sealing sleeve.






Support transmission with special tool 00 2 030, 23 0 041 and 23 0 042.






Release screws and remove cross-member (1).



Tightening Torque: 23 71 1AZ/2AZ.


Lower transmission until cylinder head touches bulkhead.

Support engine at front.

Installation:
- Pay attention to position of vibration damper (2).






Unfasten screws.
























Tightening Torque, 26 11 1AZ.


Installation:
- Replace self-locking nuts.
- Tighten mounting screws of flexible disk on transmission flange by means of nuts only.






Grip propeller shaft and release nuts.
























Tightening torque, 26 11 6AZ

Bend propeller shaft downwards at center bearing (1).

Detach propeller shaft from transmission output flange and tie back to side on vehicle underbody.






Lever out retaining ring (1) with a screwdriver.

Push retaining ring (1) forwards slightly.






Drive out retaining pin (1) on selector rod linkage with special tool 23 0 240.

Note:
To remove retaining pin (1): slide selector rod into transmission.






Release screws on actuator.









Tightening Torque: 23 41 1AZ.






Release screw (1).

Installation:
- Replace screw (1).

Release screw (2) on actuator.









Tightening Torque, 23 41 4AZ.

Remove actuator.

Important!
Hydraulic lines and cable plugs remain connected.






Unfasten screws.






Tightening Torque, 23 00 1 AZ

Important!
Do not allow transmission to hang off on transmission input shaft when removing and installing, as the clutch disc will be deformed.

Pull out transmission towards rear as far as possible, turn approximately 10° counterclockwise and remove.





Installation:
- Note correction position of dowel sleeves.
- Replace damaged dowel sleeves.
- Ensure correct position of cover plate.

Installation:
- Remove release unit and release lever and clean.






Installation:
- Check lubrication of transmission input shaft for sticky consistency. If grease is sticky, replace clutch plate.
- Check clutch plate for friction rust in taper splines and replace if necessary.
- Mechanically remove old grease and lining abrasion from the taper splines of the clutch disc (with a cloth).
- Then use a brush to apply a thin even coating of grease for lubricating taper splines over the entire area. Also in taper groove and on guide pin.