Is this an auto trans you're talking about, or manual trans? When you put it in gear, is your foot on the clutch pedal or is the vibration when you're letting the clutch out?
When you redo motor mounts, you will take a sloppy mount and tighten it up, so you can potentially take any vibrations that the sloppy mount let the engine flop around and as the engine is held more secure, the vibration will go into the chassis.
Everybody else lists their cars here - but not me.
I have too many to count