Mysterious Dirty red fluid

I see drips of red on the bottom of my tranny pan. However it doesn't look like its coming from the gasket seal. I see the same red fluid on a 2x4 box attached to the front of the tranny. What is this "box" and where do I have this leak at? Also red fluid on the "checkered" thing behind the tranny and on the leftside of the tranny on the side plate behind the tire. I hear a "thud" when I shift from park to reverse. My brakes also need to be changed. Could this red fluid be brake fluid leaking?