The last week my 250 7.3 has been doing alot of bouncing, I was under the truck this morning and found that the shock hangers attached to the rear diff. were loose, and the hanger on the drivers side had been rubbing against the brake line. This was an easy fix, but is it a thing I will have to start checking?
Thanks

 

It's not common, but some things, like those hangers, seem to get overlooked during assembly inspection...

I would check it at least once a month for the next few months. Did it damage the mounting holes? If it did you might want to check the junk yards for another set just in case.