Sometime my 2004 Caravan's rear drum brakes will stick while parked (even
with no parking brake applied, generally in damp weather). When this
happens, they let go with a "clank!" (or "clunk!") as I start to back up.
When new, this was so bad they were "fixed" under warranty (apparently the
factory screwed up something in the original rear drum brakes). Now I just
make sure (a) I don't use the parking brake (unless *absolutely* necessary)
and (b) try to have the vehicle roll back a bit in park after I take my foot
off the brake pedal (I park on a slope). Seems that if the last thing when I
park for the night is having the brakes applied, with no free roll in park,
with damp weather, the problem re-occurs...
Could be your rear drums are sticking.....

I don't know who asks more questions than I do, but that's what comes
from being an amateur.
I get a strange and rather loud snapping sound when I put my 2001
Dodge Caravan in gear and go either ahead or back AFTER the vehicle
sits for an extended period of time. I hear it just that one
time........it SOUNDS like its coming from the rear of the vehicle,
but I know how sound can "travel."
I wonder if a brake shoe could be sticking...the vehicle will coast in
neutral, though. I don't use the parking brake..could something to do
with that be seizing up a bit maybe??
I know  its nearly impossible to guess  but.....any suggestions at
all?????
Thanks
Dodger