What gets me is I'm not hearing any bearing knock or loud whining but I do have a vibration u can feel at around 30 mph then goes away and has been there since day one but I'm not sure it's related to the tranny and it's feels like a driveshaft out of balance or a universal not sure though just baffled what that metal piece is

 

Post some pics, might help to at least narrow down what it could be.

 

 

Ain't no circlip for sure.. Looks like part of a bearing lip that may have cracked.

 

Very well could be and wonder what caused if that's the case? I just wish it would fail before I get out in a remote area somewhere and it decide to take a crap lol