I just found out that my left rear axle's "clamp" is broken. My left tire I guess bounces and the mechanic told me that it could slide right out and bascially fall of my car and cause damage (among other things).

Where do I look to buy a rear clamp? They said that is all I need. Is there another name for it?

And last, but not least...how difficult is this to replace. I know the mechanic will be expensive and it looks easy to repair by myself....but I would like some more experienced opinions.

Thank you.