Assistance please,
My 1999 W202 C240 V6 M/Benz has a nagging problem with vibration when cold and stationary, when drive "D" selected a vibration is noticeable in "R" but not as bad as "D" The car has run 280,000 km trouble free. Transmission was serviced by the dealer @ about 250 000 km (filter and oil replaced)
This vibration diminished as the motor and box warm up after about 20 km and is undetectable when the machine is hot.
I have checked the CV joints and motor and box mounts for damage. All seems in order. I can't check the oil level in the box as it can only be checked by the dealer they state it is correct. The quality of the dealer's
mechanical ability is poor and they have on explanation for the problem.

for better answer.

Engine mounts would be my first guess. At that age and especially at that mileage, they're bound to be suffering.