[withamc]

Water pump. As stupid as this sounds, I had the same thing happen to me. I thought I had a cracked freeze plug, so I took it to the dealer. Turns out the water pump was leaking and running along the block to the back and dripping down. Maybe try parking facing downhill and see if it still leaks from the back. OR - heater hoses? Right above the back of the block?

 

[withamc]

I know the was on my Mustang, I haven't had the 4.0 out yet so I don't know. I would think so.