Engine Vibrations, 2001 Altima

[bcemail]

I've been experiencing a lot of engine vibration, whenever the car is in drive or reverse, but not in park or neutral. I can feel it in the steering wheel, pedals, and seat, especially when idling (not sure if it goes away when I'm moving, or if I can't feel it as much).
Any ideas what might be causing this?? I'd like to have some possibilities so I'm not going into the repair shop blind.

thanks for the help!

[nissandoc]

most cases is the front engine mount and possibly the lower mounts