Transmission fluid is cheap. I drain the contents of my pan, about 2 litres, every 3 months or less, and top it up. Is this stupid cheapskatedness or what? So far so good.

I have heard horror stories of guys with Mercedes Automatic transmissions who have changed fluid only to have the entire freaking transmission fail within a month. Whats with that?

I am sorry, but my old 123 is a $5000 car. I am maintaining it on the cheap. While I wont scrimp on the quality of the motor oil or the drain intervals, I won't pay stupid money to keep it running reliably. Why change tranny fluid when perioidic replacement of a bit of fluid at a time is working; especially given the news that a fluid change caused a failure to a poster to this forum a while back. Am I a fool or what?