Thursday, October 15, 2020

******** Audi A8L Quattro Sedan (4E8) V8-4.2L (BVJ) Technical DIAGNOSIS AND REPAIR # 391003 Date: 100629


A/T, Drivetrain - Vibrations On Tight Turns



37 Vibrations on tight turns



39 10 03



2022896/1



June 29, 2010



Affected Vehicles



203



Condition



Customer may report vibrations, humming noises or rubbing noises from the drivetrain when driving slowly around very tight turns. The noise is



particularly noticeable when maneuvering at full steering wheel lock in a parking lot.



Technical Background



Friction-reducing additives in the differential oil are reduced by wear. At high load on tight turns, the friction discs and worm wheel teeth in the



center differential are subject to wear.



This changes the friction and locking values in the center differential and causes vibrations in the drivetrain.



Production Solution



Service



Test drive the vehicle.



^ Light vibrations at full steering wheel lock are normal.



^ With stronger than normal vibrations in minor corners or heavy vibration at full steering wheel lock, proceed as follows:



a. Check the center differential according to the repair manual for correct oil level and inspect for damage (metal shavings).



b. Ensure the wheels are not damaged (bent) and all four tires are the correct size and the same type of tire.



c. If nothing is found, change the oil of the center differential with G 055 145 A2.



The center differential does not have a drain plug, therefore the gear oil can be drained only by removing the cover.



Follow the repair manual directions for removal and installation of the Self-Locking Center Differential Cover but only remove the cover far



enough to drain the oil. Then reassemble and fill with the new G 055 145 A2 oil.



d. Drive the vehicle along a lot of bends until the gearbox temperature reaches 80锟斤拷C and reassess the vibrations.



- If the vibrations have been reduced to normal, the concern is repaired.



- If the oil change does not repair the concern, submit a Technical Assistance Center ticket under the Concern Type: Audi Automatic



Transmission.



Warranty



204



Required Parts and Tools



Additional Information



All parts and service references provided in this TSB are subject to change and/or removal. Always check with your Parts Department and service



manuals for the latest information.