When I brought in my Prius last week for the 30,000 mile maintenance, I mentioned a "creaking" sound when I hit bumps. The dealership said I had a bad steering assembly and they replaced it at no charge. Unfortunately, I still have this "creaking" sound. My Prius sounds like a 1945 pick up truck when I turn into my driveway or go over a bumpy section of road. It almost sounds like a suspension thing? Has anyone experienced this sound?