27 21 020 Replacing radial shaft seal for output flange (ATC 35L)

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Special tools required:

27 1 440

IMPORTANT: After completing repair work, check TRANSMISSION OIL LEVEL and top up if necessary.
Use only the approved transmission oil. Refer to 1.0 TRANSFER CASE OPERATING FLUIDS .

Necessary preliminary tasks

Disconnect PROPELLER SHAFT at gearbox, release center mount
Tie back propeller shaft to underbody
Note:
An excessive deflection angle of the propeller shaft may damage the joint/propeller shaft!
Support gearbox with jack when removing the transfer box.

Release circlip (1).

Fig 1: Identifying Output Flange Circlip

Courtesy of BMW OF NORTH AMERICA, INC.

Release output flange with three-claw extractor tool.

Lever radial shaft seal out of housing with a suitable tool.

IMPORTANT: Do not damage housing.

Fig 2: Removing Output Flange With Three-Claw Extractor Tool

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note:

Replace O-ring in output flange.

Check that O-ring is in correct position.

Fig 3: Identifying Output Flange O-Ring

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note:

Coat sealing lips of new radial shaft seal with clean transmission oil.

Drive in radial shaft seal with special tool 27 1 440.

Fig 4: Installing Radial Shaft Seal Using Special Tool (27 1 440)

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note:

Push on output flange
Press output flange towards the bottom using 2 screwdrivers.
Mount shim.
Continue pressing output flange towards the bottom until retaining groove is completely visible.
Fit circlip.

Fig 5: Pressing Down Output Flange Using Screwdrivers
Courtesy of BMW OF NORTH AMERICA, INC.