Hi all, new to the site, ok I have a 2008 e280 cdi sport, its recently developed a vibration when in reverse, pretty bad and I could hear a knocking noise that sounded like it was under the gear selector when starting the car from cold, I took it to a garage and they had a quick look and gave me a bit of "free" advice, I had play in the centre prop bearing, which ive had changed along with rear gearbox mount just for good measure, the vibration is still there, quite bad in reverse and when in park on idle, but not in drive, unless i coast, once car has been driven for 10 mins and its up to temp the vibration isn't there at all and its all normal, gears are smooth, no jerking, no over heating, no struggle through gears, any advice or help in the right direction would be much appreciated, cheers