Okay, for the last few days, ever since I got back from california and my car sat for a week, I've been hearing what sounds like the muffler dragging against the ground coming from the back half of the car, but the problem is, it does it when standing still and even in park, I looked underneath and nothing'* dragging on the ground, I can't isolate the noise to a specific place because it'* only for a minute or so at a time. Any suggestions on what it could be or where to check?

Hard to say just off of that description. Standing still wouldn't make any sense for moving parts, so the only thing I can think of would be your ELC compressor. Is your car equipped with ELC? or are you certain that its on the underside of the car. Theres not a whole lot else that can move back there while standing still. While moving I could say anything from bearings to brakes. If you do have ELC, be sure to check that.

I'll see if I can get a video of the noise happening today while I'm out to help diagnose it.

The only two things that can make noise at the back of the car while not moving are your ELC pump (Right Rear wheelwell) and fuel pump (in the tank).

Probably the ELC pump then, cause it seems to come from the right side and it'* louder when the windows are down. Any idea what could be wrong that it'* making a grinding noise? I've heard it turn itself on before and I've never heard it grind.

Probably two-fold if that'* the source of the noise. Air leaks in the strut system somewhere, and a failing pump.

Well, the SES light came on today, which may be what was the grinding noise, as the code that pops up is :
DTC P0742 TCC System Stuck On
The grinding noise just may well have been the torque converter.... Any ideas on what would fix this or where to go from here?

the TORQUE CONVERTOR? I doubt thats the problem. The torque convertor is what transfers the spinning power of the crankshaft to the transmission. In the FRONT of the car on the drivers side of the engine. If its the rear, its definitely your ELC.

I know what and where the torque converter is, just kinda figured that it might be the problem since sounds tend to be hard to pinpoint when you're inside the car and I've not been able to be outside of it yet while it'* grinding to be sure.

it is very easy to eliminate the elc. turn the key to "run" , go to the right rear of the car and listen. when the elc compressor turns on (about 10 seconds after key on) you will know.