23 00 028 Removing and installing transmission (GS6-45BZ) (N55) 4WD

Special tools required:

IMPORTANT: To prevent heavy damage to the engine block, the protruding thread of the transmission bolts absolutely must be checked for damage and corrosion before removal .
If there are signs of corrosion, the rust must be removed and the threads must be cleaned before removal .
Replace rusted, damaged screws.

Failure to comply with this instruction will result in serious damage to the engine block and transmission.

IMPORTANT: After completion of repair work, check TRANSMISSION OIL LEVEL .
Use only the approved transmission oil. See MANUAL TRANSMISSION -- OPERATING FLUIDS .

Failure to comply with this requirement will result in serious damage to the manual gearbox.

IMPORTANT: For vehicles with N54/N55 engine up to production date 09/2012, aluminum bolts for the for the securing of the transmission are also installed.
As of production date 09/2012, only steel bolts are installed for the securing of the transmission.

NOTE: Aluminum screws/bolts must be replaced each time they are released .
Aluminum screws/bolts are permitted with and without color coding (blue).
For reliable identification:
Aluminum screws/bolts are not magnetic .
Jointing torque and angle of rotation must be observed without fail (risk of damage) .
The aluminum bolts can be optionally replaced by steel bolts.

Necessary preliminary tasks

Remove UNDERBODY PROTECTION at front and rear
Remove REINFORCEMENT PLATE
Remove EXHAUST SYSTEM
Remove heat shields
Release hose sockets from charge air cooler on left and right
Disconnect coolant hose from front axle
Partially release PROPELLER SHAFT
- Disconnect propeller shaft from transmission
- Release center mount.
- Tie back propeller shaft to underbody
  NOTE: Bending the propeller shaft by an excessive angle can cause premature damage to the joint/propeller shaft!
Support engine with jack when removing gearbox

Remove upper part of cable duct (1).

Fig 1: Identifying Upper Part Of Cable Duct

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Remove holder (1-3).

Fig 2: Identifying Holder

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Release screws (1).

Tightening torque: 26 11 9AZ .

Remove front propeller shaft at output flange of transfer box and tie to one side.

Installation note:

Replace screws.

Fig 3: Locating Front Propeller Shaft Screws

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NOTE: Pressure line of clutch slave cylinder remains connected.

IMPORTANT: Relieve tension on clutch slave cylinder slowly; otherwise air will be drawn in through sealing cup.

Release nuts and remove clutch slave cylinder.

Installation note:

Replace self-locking nuts.

Tightening torque: 21 52 5AZ .

Fig 4: Locating Pressure Line Of Clutch Slave Cylinder Connection

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Detach connector (1) from reversing light switch.

Release cable from brackets.

Fig 5: Identifying Reversing Light Switch Connector

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Release screws (1).

Remove holder (2).

Fig 6: Identifying Holder And Screws

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Release screws (1).

Disconnect connector (2).

Steel screws, tightening torque: 23 00 1AZ .

Aluminum screws, tightening torque: 23 00 2AZ .

Release aluminum screws with special tool 00 9 010 .

Fig 7: Identifying Connector And Screws

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Supporting transmission

Support transmission with special tools 23 4 050 and 00 2 030 .

Secure transmission to mounting with tensioning strap (1).

Tasks are described in Transmission bracket. See 23... UNIVERSAL BMW TRANSMISSION TAKE-UP .

Fig 8: Identifying Tensioning Strap

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Remove screws and nuts.

Remove transmission cross member.

Tightening torque: 22 32 4AZ/5AZ

Fig 9: Identifying Transmission Cross Member Screws And Nuts

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Disconnect plugs (1) and (2) from servomotor.

Fig 10: Identifying Servomotor Plugs

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Lift off retainer (1).

Detach gearshift rod (2).

Installation note:

Grease gearshift rod.

Grease,

Refer to BMW Service Operating Fluids. See MANUAL TRANSMISSION -- OPERATING FLUIDS .

Fig 11: Detaching Gearshift Rod

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IMPORTANT: Retaining clip must interlock captively with retaining web (1) behind gearshift rod pin.

Fig 12: Identifying Retaining Web

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Unlock bearing journal (1) in direction of arrow and remove.

Lift out gearshift arm.

Installation note:

Grease bearing journals (1).

Grease, refer to BMW Service Operating Fluids. See MANUAL TRANSMISSION -- OPERATING FLUIDS .

Fig 13: Removing Bearing Journal

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Release screws.

In vehicles with an N54/N55 engine from production date 09/2012, only steel bolts are installed.

Steel screws, tightening torque: 23 00 1AZ .

Aluminum screws/bolts (3, 4, 5, 9, 10), tightening torque: 23 00 2AZ .

IMPORTANT: Do not allow transmission to hang on transmission input shaft when removing and installing, as the clutch disc will be deformed. Pull transmission downwards and remove.

Fig 14: Transmission Housing Bolts Tightening/Loosening Sequence

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Installation note:

Tighten down screws/bolts to specified torque.

Special angle-of-rotation tool 00 9 120 with magnet 00 9 130 .

Secure to vehicle underbody and screw down aluminum screws/bolts in accordance with angle of rotation.

Angle of rotation 23 00 2AZ .

Fig 15: Tightening Transmission Screws/Bolts

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Installation note:

Check that fitting sleeves are correctly fitted.

Replace damaged fitting sleeves.

Ensure correct position of cover plate.

Fig 16: Identifying Fitting Sleeves

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Installation note:

Check lubrication of transmission input shaft for sticky consistency. If grease is sticky, clean input shaft and REPLACE CLUTCH DISC .

Check clutch plate for friction rust in splines and REPLACE if necessary.

Mechanically remove existing grease and lining abrasion from gearings of clutch disc (with a cloth).

Fig 17: Locating Lubrication Of Transmission Input Shaft For Sticky Consistency

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Installation note:

Greasing specification:

Remove and clean RELEASE BEARING AND RELEASE LEVER .
Push on grease scraper ring 21 2 240 until limit position.
Grease gearing (1) of input shaft. See MANUAL TRANSMISSION -- OPERATING FLUIDS .
Detach grease scraper ring.

Fig 18: Locating Grease Gearing Of Input Shaft
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