I chased a tranny fluid leak for some time and changed the rear seal twice before I found that it was coming from a place that I did not even know COULD leak...the slip yoke. The end of the yoke is pressed in.
http://forums.maxperformanceinc.com/...ight=yoke+leak
Of course in that instance, once I started looking frequently enough, I could see that the initial moisture to a very cleaned up area was
behind the rear seal and pan. The first drop to show was on my u-joint.
What is the furthest point forward that gets wet?
In my case, it appeared to be where someone touched a welder to it and weakened a spot that later blew out.