oldmate

The is some play is my drive shaft, as shown in the youtube video
When it put it in reverse there is a clunk, then there is another clunk when i put it in drive, and another clunk when I'm driving it it changes down. The u-joints seem good, the movement seem to be coming for the diff. Someone advised me it could just need more grease on the yolk...

Any help or advice would be awesome.

1997 F150 reg cab short box 4x4 4.2L V6 auto