I have never experienced either of these symptoms and would suggest taking the car to the dealer ASAP.
Good luck
Yes, I do experience abviuos vibration on my GS350 AWD at idle. And I spoke about it on this site 5 months ago.
I have made a big fuss about it with my dealer and the Lexus Customer Satisfaction office. They sent a factory representative to investigate the problem..
The representative measured the vibration level and proclaimed that the level is “within the specifications”. I received a letter which states that my car is “normal”. The end of the story!
During this appointment I have checked out 3 different GS350 AWD’s and all of them have had similar level of vibrations. But a GS460 did not have ANY vibrations.
During my conversation with the representative he explained to me that only 6 people complained about this type of vibrations and of cause this is not a substantial number for Lexus to take actions.
What should we do as a community?