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.

Tighten screws crosswise.

Tightening torque 33 11 4AZ  . See 33 11 REAR DIFFERENTIAL CASE WITH COVER .

Fig 1: Identifying Side Cover And Markings

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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 And Ring

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Installation: 

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

Fig 3: Identifying Contact Surface For O-Ring

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Replace O-ring (1).

Installation: 

Keep drain opening (2) for gear oil clean.

Moisten O-ring with approved differential oil. 

Fig 4: Identifying O-Ring And Drain Opening

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After installation: 

• Check rear differential oil level  , correct if necessary