the aftermarket trans filters dont seal the filter to the pickup tube which causes air to be sucked and causes the pump noises.
The valve body rebuild can be done yourself, or he can send one already rebuilt with a core charge til he gets it. The valvebody upgrade should be done weather you have problems or not. I dont concider it blind heart surgery and it is do-able even with someone with limited experience...follow the directions.
Basicly, the whirring is simply air sucking in.
95 E34 530I V2.37
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