Metal in rear diff

I wouldn't classify that as swarf. Usually machined components go through a high pressure deburr washer to knock crap like this loose and wash it out. ... Obviously they aren't doing that or they aren't doing it correctly.

 

That would still would make it swarf just means their industrial process for cleaning isn't sufficient.

 

In my experience swarf is usually fine chips or metallic powder.
Meh.