(A4BF1/A4BF2*/A4AF2/ A4AF3) are known to have an inherent flaw in which causes the overdrive clutch bearing to disintegrate due to too much inplay from the factory. This causes issues shifting into 4th gear, or while driving in 4th gear causing the vehicle to throw diagnostic code PO734.
If you DO NOT install the shim the issue will happen again. The shim is key. We also recommend replacing your filter and pan gasket due to the broken bearing particles.