33 11... Replacing O-ring for side cover on rear differential on left or right (M3)

Necessary preliminary tasks 

• Remove DRIVE FLANGE FROM REAR DIFFERENTIAL 

Mark installation position of side cover (2) to housing.

Release bolts along line (1).

Press cover (2) with two screwdrivers off housing.

Installation: 

Markings (3) on cover and housing must match up.

Fig 1: Identifying Mark Position Of Side Cover To Housing

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Tighten screws crosswise.

Tightening torque 33 11 4AZ .

Raise mount and remove cover (1) with ring (2).

Installation: 

Insert cover with ring in housing.

Raise mount and slide in cover as far as it will go.

Fig 2: Identifying Cover With Ring On Housing

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Installation: 

Clean contact surface (1) for O-ring all round.

Fig 3: Identifying Contact Surface Of O-Ring

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Replace O-ring (1).

Installation: 

Keep drain opening (2) for gear oil clean.

Moisten O-ring with

hypoid oils for final drive unit with disc-type limited-slip differential (M models). See REAR AXLE - OPERATING FLUIDS ..

Fig 4: Identifying O-Ring And Drain Opening

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After installation 

• Check REAR DIFFERENTIAL OIL LEVEL  , correct if necessary