Question on a Ford 8.8 pinion

Been hearing some rattling and banging around when I let off of the gas in the rear. I was thinking it was something wrong with the locker. (I've never had any before, so I don't know what to expect)
But on the suggestion of some here, I went and checked the companion flange and there is definitely play in there.

I watched the below video and the play in the flange is the same as in the video.
http://www.youtube.com/watch?v=8APYO2sZyJU

Is it worth trying to tighten the flange down some? There doesn't seem to be any preload in the flange. Or maybe I don't know enough about it to judge.

Thoughts?

Have you checked the torque on tthe pinion nut?

Not with a torque wrench, no. it's hand ratchet tight at least. Maybe I should put it on youtube so ya'll can see how much play there is. There isn't any in and out play but there is some left and right. not a whole lot. It looks a lot like the video I linked to.

Lol, what do you think he is talking about?
First off define your idea of "play". There will always be play to due to backlash in a gear set. I am just a rookie but I have done this twice on an 8.8, although never with the carrier installed. All it takes is a decent torque wrench.
However "rattling and banging around" doesn't make me think of pinion bearings. I would pull the cover and see whats going on before I messed with anythign else.

I'm not talking about the rotation play. I know that's supposed to be there, I'm talking about being able to move the flange left and right just a little bit. I compared it to the front axle's and there wasn't any play up there at all. the only movement was the rotation. The rear, I stick a small pry bar in there and I get maybe an 1/8 inch of movement. left and right. Nothing in and out. When I'm driving it's quiet, when I get up to 15 or 20 miles an hour and let off of the gas there's a whole lot rattling going on, but once I put the foot down again, it shuts up. let off and it rattles again.

I don't think it's the locker in there because I can get the tires to lock up. Turning as tight as I can will chirp the rear tires. If the locker was screwed up it would be making noises constantly and not locking up at all.

The pinion should be firmly supported by the bearings and there should be no play like you are describing. If the pinion bearings are that far gone I would address it right away.

I've been reading/researching and it SEEMS like harsh/extended use will cause the crush sleeve to expand especially if it's poorly torqued. When I installed the axle I did spin the pinion and I didn't feel any roughness in the bearing. But then again, I didn't notice there was very little preload either. Since I'm planning on replacing the whole thing would it be worth my time to retorque the pinion and see if that gets rid of the play, before I pull everything apart? When I rotate the pinion there doesn't seem to be any preload on it at all. Which adds to the theory it's not torqued down well enough.

fixed it. Whoever did the work on the rear axle last re-used the pinion nut. It was way too easy to torque back down. Rattling is gone now, and the pinion bearing seems pretty solid still. no play whatsoever! Need to get a new pinion nut now.