E46 S6S 420G SMG gearbox — BMW
E46 S6S 420G SMG gearbox on BMW: 52 steps, engines S54B32. What to remove, in what order, and what to check after.
Workshop procedure for BMW — the exact step sequence and torque figures, straight from real workshop data.
🧭 Before you start
Fits: platform codes M3, CSL
Don't miss
- Do not disconnect the hydraulic lines
🔧 Engine codes this applies to
📋 Procedure
- Disconnect the battery
- Remove the air inlet manifold
- Remove the heater bulkhead
- Remove the radiator fan and shroud
- Remove the reinforcement plate
- Nuts:
- Remove the exhaust pipe with the catalytic converter
- M10:
- M12:
- Transfer box:
- M10:
- Gearbox to engine:
- Hexagonal bolts:
- Remove the heat shield(s)
- Disconnect the oil temperature sensor
- Disconnect the speedometer from the gearbox
- M12:
- Torx bolts:
- Remove the clutch slave cylinder
- Note: Do not disconnect the hydraulic lines
- M10:
- Propeller shaft middle support
- Remove the cross member under the gearbox
- Lower the gearbox slightly
- Remove the propeller shaft
- Renew the self-locking nuts
- Remove the propeller shaft middle support
- Disconnect the propeller bearing
- Disconnect the gear-shift rods
- Remove the bolts
- Remove the actuator
- Remove the gearbox bolts
- Remove the gearbox
Other BMW procedures
Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Cross-check torque against the factory manual for your engine before final tightening.
Seen a figure that does not match your manual? Write to us — we correct it and note when. support@torqfix.com
The story behind TorqFix →Workshop data on this page last updated 20 Sep 2026.