While driving yesterday there was suddenlyoo677777⁶ a loud noise coming from under my car , when I stopped to investigate i noticed a treaded bar hanging down from under the drivers door it was rubbing off the ground, I'm not sure what it is? I managed to shove it back up into the car a tuck it in so it doesn't fall down again, it doesn't seem to have affected the driving performance and there are no warning lights on the dash? Can anyone tell me what this is? Thank you