hey everyone - anyone have any idea what this could be? Has been happening for a few weeks now. As i slow down i can hear a knocking coming from the back of the car. But now it sounds like it's happening throughout the car. ha, great huh? I'm wondering if it's something to do with rotors, or rust...something in that area. I'm actually looking to sell it soon (getting another Mazda), so instead of fixing it, I just wanted to be able to explain to the potential buyer what it could be (and also how much they could expect to pay to get it fixed). It seems to drive fine besides that though...thanks in advance!