Yes that's what happened to me, the back would get all jittery around corners and over small bumps. I took out the back suspension and after I undid the pillow mount bolt on one of the shocks to get the spring off the shocky collapsed, I could push it all the way down and it would just stay there and when you lifted it all the way up and jiggled it it would fall down all by it's self.
I had previously taken the car to Pedders and they said that they where soft but other then that they where fine.