Vibrations/Wobble in park and neutral

[skibummin101]

My 2005 V6 with 170k is giving a very distinct wobble/vibration when in park or neutral. When I shift into gear it completely goes away and feels really smooth. It is pretty significant, to the point of annoying/nauseating after a few minutes.
Any advice on where to start trouble shooting would be greatly appreciated.
Thanks in advance!

 

[fdbyrne]

Engine mount?

 

[Jeremy03Sport]

Following...mine does same...

 

[Jeremy556]

Check transmission and engine mounts.