Unreadable Disk Util shows 4.14 GB drive is 1.5TB

Unreadable Disk Utility is showing that one of my internal drives is 4.14 GB when it is really 1.5TB. Drive may have failed, when I restart computer, drive clicks a few times and error message Disk Unreadable, Initalize, format ignore comes up. Before I trash it I wanted to be certain there is nothing else I can do. This drive is not the start-up disk and "has" SnowLeopard Partition. MacPro start-up disk is running 10.7.4 I have moved it to other bays - no change. No back up and it doesn't contain critical data, but if I can get the OS with my user settings or even just my user folder off of it I'd like to try before trashing it.

Disk Utility and Disk Warrior did not help

gpt recover: unable to open device '/dev/disk0': Input/output error

Any suggestions? Or is this drive done?

Thanks

Betsy