So I just changed my transmission fluid and it appears that it has begun to leak. First of all I put in about three quarts and it began to leak out of the filler plug so I stopped and put the plug back in. Then a few hours later i saw a huge puddle under the transmission and checked it out. It looks like it is leaking from where the axel connects to the transmission. It didn't do this before so I'm wondering if I over filled the transmission or what. If any one can help that would be greatly appreciated.

You put three quarts in. How much originally came out? If it was less than three quarts maybe the level was below where you're now seeing the leak.

Yea it didn't seem like 3quarts came out but I read some where that it takes 4. I guess I don't know how much you are supposed to put in?

This one's easy.
Total capacity is 2,5 liters...

You are to fill it until it reaches the fill hole. If the rear is elevated very high when filling, then you will over fill. It is possible. The puddle is a good sign of this.