Spinning means it is getting power, but does not mean it is properly seated with regards to the data connection. Really anxious for you to get to the bottom of this so I can ask you if you notice the same increase in heat and vibration with one. Temps seem to be up 5-6 degrees Centigrade at idle, and a bit more vibration can be felt.
It will be automatically detected, however, if the drive is new it will be unformatted, that means you won't be able to see it in Finder. Go to Disk Utility and see if the drive is listed there, if its not, chances are its a problem with the disk, if so, RMA it.