Recently took all of my mats out and removed my plugs to hose the interior out, and there was green liquid that looks like the antifreeze I run in the passenger tub that had dripped down from the tranny doghouse under the dash. Any clue where this could be coming from or what it is exactly.

 

My heater core went the other day and this happened.....among other things. Maybe just a loose line if youre having no other problems.

 

A leak in the heater core can cause coolant to drain out into the passengers floor board.