I've always just stuck my finger in there & tried to rotate the inner race. If it goes easy, it's probably still good. However, it's pretty cheap to replace, just go ahead and do it. A lot of people say it's a bear to get out, but I have always had no problem using a slide hammer w/ a bolt attachment. I took a bolt that screwed into the hammer & ground off one side of the head, leaving a little tab on one side, placed it behind the bearing, & pulled it out. Make sure to put some heavy grease on the input shaft when you re-install the trans, to make it easier to seat.
