Help! I am getting very loud noise from my c180 saloon. The noise appears to be from the front and occurs when I slow down the car to about 20 km/hr. It sounds like something is being dragged on the road. Once I increase speed, the noise seems to disappear. However, when i reach 60 km/hr, alas! the noise comes back again. Any idea what is the problem? Thanks in advance for the help!