My Buick with its 3800V6 has a little bit of a "buzz" at idle. Just enough for me to feel through the steering wheel and shake the rearview mirror. This is annoying to me, and I wish I couldn't feel the engine at all. I know there are some cars out there that you can't feel (or hear for that matter) idle at all. The brand Lexus comes to mind. What about your car or truck, what kind of idle do you have?