Loud squealing/creaking noise coming from rear

[Cduncan133]

Hello, I'm new here and have been shadowing for awhile now. Recently, I've come across a problem with my 04 Explorer. I hit a small pot hole on my home from work, and now I hear this painful squealing noise coming from the rear drivers side. I guess the only way to describe it as a sound similar to an old door that makes a "creaking" sound, but in a higher pitch I guess. Here's some pics:

 

[Number4]

Jack up the rear and see if the wheels have any play.

Also look at the strut springs to see if one snapped.