...fell off!!! Following this thread ( http://www.mbclub.co.uk/forums/engine/117207-w210-e320-cdi-alternator-pulley.html ) posted yesterday. Today the pulley fell off. The pulley started chirping on Sunday. On Monday my Indie advised it was the alternator pulley. I started my research yesterday re: getting a new one. But events overtook me. Last night the noise became a constant grinding which my daughter said could be heard a mile off. So, I cancelled my diary this morning and had my wife follow me to the garage. On the way the red alternator warning came on, so I congratulated myself for going to the right place. Then the power steering went off. Then all went quiet, followed by a rattle and something hitting the underside of the car. So, I guessed the belt had come off (and maybe the pulley too). I was only 2 miles from home with a mile to go, so the engine was only warming up...but the temp then started to rise quickly. I drove on. By the time I got to where I was going the temp was just below 100. We opened the bonnet, the belt was indeed off...and so was the pulley. Anybody ever had a similar experience?