Picking up my transmission saga: oil analysis showed contamination of the trans fluid by water but not antifreeze, leading me to suspect that the radiator was fine but water infiltrated while the trans pan was loosely attached. There’s no easy way to completely drain the transmission - the pan only holds about a gallon, the whole system holds three, and the upper radiator cooler hose is too small to pour enough fluid in to flush the torque converter. So I hit on the idea of doing several standard drain/fill cycles. If I do six, if there were a quart of water in the system to start with, would dilute it to about two ounces. Is that good enough? I figure I probably couldn’t do much better even with a pro machine flush.

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1998 A8Q 143k