Some drives can be diagnosed with S.M.A.R.T. and warn of an imminent failure. I had this actually work one time. Was nice when I got a decent warning. I backed everything up and then kept the drive in service in a non-critical area and it completely failed a few weeks later.

If the drive is clicking it is likely going to expire soon. I would get as much data off of it as you can and then search for a replacement. If it is still under warranty you would want to RMA it.