Hi Dana,
I also have the squeaking in back. When ever I start to slow down to stop sign or traffic light under 20mph, I hear a squeaking sound, not a braking issue as it happens when slowing down with or without braking. Also squeaks when I start to accelerate from slowing down, but once get above 20mph there is no squeaking. I've been told it could be suspension related probably rear trail arm bushings, which I plan on replacing before spring sometime. Please let me know if discover another possibilities.
Thanks,
Alex