Odd vibration on W140

[A. Rosich]

I just changed the two engine support mounts and the rear transmission support mount on my 1998 S 500 L.

The new mounts provided an extraordinary improvement on smoothness of operation at all levels EXCEPT when standind still, with "D" engaged on the auto trans. and the
brake applied.

There is an odd continuous vibration that it is easily perceptible at the steering wheel, the main dash area and the front driver's and passenger's footwells. This vibration was not present before changing the mentioned supports. Also, the vibration completely dissapears if I switch the transmission to "P" and lessens considerably if switched to "R".

Any guesses on what could be wrong???

Could the new supports not be properly fastened or I am missing and additional support that I did not replace?

Thanks in advance for your input.