General Repair Information: Components

Transmission 

• Make sure that the alignment sleeves between the transfer case and transmission are positioned correctly when installing the transfer case.
• Clean the contact surfaces when installing the brackets as well as any waxed components. Contact surfaces must be free of grease and wax.
• For the correct bolts and other components, refer to parts
• When replacing a transfer case, the gear oil must be filled up to lower edge of filler hole. Refer to TRANSFER CASE, CHECKING TRANSMISSION FLUID LEVEL .
• Capacities and specification in the transfer case. Refer to TRANSFER CASE DESIGNATION 0BU 
• When replacing a front final drive, the gear oil must be filled up to lower edge of filler hole. Refer to AXLE OIL LEVEL IN FRONT FINAL DRIVE, CHECKING .
• Capacities and Specifications, Front Final Drive. Refer to CODE, TRANSMISSION ALLOCATION, RATIOS AND CAPACITIES .
• When replacing a rear final drive, the gear oil must be filled up to lower edge of filler hole. Refer to REAR FINAL DRIVE AXLE OIL LEVEL, CHECKING .
• Capacities and Specifications, Rear Final Drive. Refer to REAR FINAL DRIVE DESIGNATION 0BN AND 0BP .

Sealant 

• Thoroughly clean housing joint surfaces before applying the Sealant AMV 174 004 01.
• Apply the Sealant AMV 174 004 01 evenly and not too thick.

O-Rings, Shaft Seals, Sealing Rings and Seals 

• Replace the O-rings.
• The open side of the shaft seals point toward the fluid to be sealed in.
• When installing the new shaft seals, make sure the sealing lip does not run on the same point as the sealing lip of the old seal (use insertion depth tolerances).
• Lightly lubricate O-rings before installing to prevent them from being crushed when inserting.

Shaft Seals 

Fig 1: Identifying Oil Seal Sealing Lips

Courtesy of AUDI OF AMERICA, LLC

Prior to Installing:

Lightly coat the outer circumference with oil and then fill the space between the sealing lips -arrow- halfway with Sealing Grease G 052 128 A1.

After Installing:

• Check the transmission fluid level in the transfer case. Refer to TRANSFER CASE, CHECKING TRANSMISSION FLUID LEVEL .
• Check transmission fluid level in front final drive. Refer to AXLE OIL LEVEL IN FRONT FINAL DRIVE, CHECKING .
• Check transmission fluid level in the rear final drive. Refer to REAR FINAL DRIVE AXLE OIL LEVEL, CHECKING .

Fasteners 

• Do not overstretch the circlips.
• Always replace damaged or stretched circlips.
• The circlips must fit completely inside the groove.

Bolts and Nuts 

• Tighten and loosen the bolts and nuts for securing covers and housings in a diagonal sequence.
• The tightening specifications stated apply to non-oiled nuts and bolts.
• Always replace self-locking nuts and bolts.
• Make sure the contact surfaces and visible surfaces on the nuts and bolts are waxed after assembling.
• Use a wire brush to clean the threads of bolts that were screwed in with locking compound. Next, use Locking Fluid AMV 185 101 A1 to install the bolts.
• Threaded holes into which self-locking bolts or bolts coated with locking fluid are screwed, must be cleaned (e.g. tap). Otherwise there is a risk that the bolts will shear the next time they are removed. Pay attention to the thread pitch when cleaning with a thread cutter.

Bearings 

• Install needle bearings with lettered side (thicker metal) racing the fitting tool.