Transmission Output Flange Bearing ?

[lexus400]

I have a '92 ES which I sold to a friend of mine a couple of years ago. The trans was rebuilt and has about 40k miles on it. He called me because he was getting a noise coming from the front when driving. At first I thought it was a CV joint but when I looked underneath the output flange that connects to the axle (the inner CV) has a lot of play in it. It moves up and down and even has some play in/out.

I am hoping that just the output flange is loose and that the center bolt needs to be tightened but I think that it might be the bearings in the transmission. Anyone else had this problem before ?

Bob