Hi All I brought an 03 w209 CLK55 a few months ago on the cheap as it needed some work. One issue is that there is a noticeable clunk from the rear if you shift from park to drive or park to reverse. When driving the gearbox changes are smooth. How ever if you accelerate hard there's always a knock and a feeling of lag, you get the same sort of knock if you ease off the throttle. I have taken a video of it here: Does this look like a new diff is required?