Rear end issue?!
 

I have a loud whining noise coming from the back of the car and a grinding/moaning coming from there after driving for a period of time and expecially when turning or going in reverse. Any ideas?

Are we talking about a car or a person?

List your mods and any information about when it occurs like ambient temp, drive time, etc

lol, no its not a person. Currently only have a steeda CAI, sct 93 tune, o/r xpipe, pypes pype bomb axle backs. Rear end is stock and has never been touched. The whinning starts a 2500rpm + the grinding starts to occur after about a half hour of driving. Always grinds in reverse

And I can feel the grinding bad at low speeds. Once it gets going you can no longer feel it but it is noisy as hell. The oil level is fine just check it and there are no metal shavings on the plug mag.

Have you hit potholes, curbs, or other hard objects? (Or backed over something that scraped your dif?)

Yeah there are so many pot holes here that you cannot miss all of them. The roads here completely suck.

I wonder if you hit something hard enough to unseat a component in the rear differential.

If it sounds like it is going to look like this:

http://www.gearinstalls.com/sam_files/sam1.jpg

Get it looked at by someone with experience or a shop.

Is there any damage under the car or scrapes?

No scrapes or marks. Im going to see if I can drop it off tomorrow. It drives fine but is noisy as hell and grinds. I just hope it doesnt cost too much

Any fluids on the cover itself or the ground?

take it to a differential specialist if you can find one near you. Usually they are alot better, and cheaper than the dealers