These pieces came out of my rear differential. Some of the debris look like clips. Any ideas?

[IMG]local://upfiles/28040/EAD6707C84064653AD3EC75EFEF16D95.jpg[/IMG]

 

The smaller parts look like the retaining clips or whats left of them for an LSD clutch pack,the larger piece looks to be part of a clutch pack ring.The parts in your pix look like they have made the rounds in your diff, I'd be checking things out in there if I was you.
Added:
I just saw you had another post about your diff leaking, probably due to the metal debris cutting the seal,if the debris made it to the seal it probably took a tour thru the bearings/gears,you really need to check it out. If the metal pieces are parts of a clutch pack,it will continue to break apart and could lock up the rear end if the gears pick it up or you could lose an axle.Most of the time it is the clutch pack ring that pushes on the axle/spider gear that breaks[the one nearest the gear],you should be able to check it using a flashlite to see in there,if a few of the rings break and fall off the axle shaft then you could lose an axle c-clip and then the axle.

 

I put 200km on it today and even some 4x4. It seems to be working fine. How can I tell if I have an LSD? (or do they all have em?).

 

Jack up the rear end and spin one side. If you can spin the tire and the other one rotates the opposite direction, it is regular differential. In Park, if you can't spin either wheel, it is an LSD. But if there's no tension on the clutch pack, it may react as an open rear.

 

Thats a bad way to determine if you have an open diff or if you have LSD. My tires spin opposite directions and I have LSD, the clutch packs are just getting worn out. That doesn't really work for LSD though, Posi or a Locker sure.

Look under your hood or in the door jam and there should be a list of some of the options the truck has. On mine its under the hood say says I have the limited slip diff.