New here with a 2004 C5 and recently I've noticed in the mornings a few drops of ATF on the floor of my garage?? So last weekend I jacked up the car and found that the leak is coming from around where teh transmission connects to the rear differential? So I removed the plug and then noticed that it was overfilled? (Dealer did last service, not me). I let it drain till it was right where it needed, I'm no expert but it looked like the overflow tube and top of the transmission was dry? With it being a little overfilled if the fill plug was not getting a seal is this something to worry about? Has anyone noticed or experienced the same?