Trans Am

Ok, So I've had this loud annoying spueak/ knock coming from the right rear for a long time. I can push on the rear of the car outside and i can hear it... I've pulled off the control arm and lubed the body side bushing up as well as the axle side. The noise stlil continues...I know my axle is already busted, the differential is broken...but if i push on the left rear i don't hear it. So i can't really come down to a conclusion on what it really is...I used to have BMR boxed subframes on my car and now i have the LG motorsports SFC with X brace. Its been happening during both subframe connectors...Is it possible that the control arm is broken inside???