A Seagate Desktop 4TB drive connected via FW800 (have tried USB 2.0), same problem.
OSX cannot repair, mount or delete the greyed out (un-mountable partition).
Nov 12 10:58:54 kernel[0]: hfs_swap_BTNode: record #-1 invalid offset (0x0000)
Nov 12 10:58:54 kernel[0]: hfs: node=13216 fileID=4 volume=Backup001 device=/dev/disk4
Nov 12 10:58:54 kernel[0]: hfs: Runtime corruption detected on Backup001, fsck will be forced on next mount.
Nov 12 16:54:03 kernel[0]: CoreStorageGroup::completeIORequest - error 0xe00002d9 detected for LVG "Backup001" (547C5767-6075-4522-8138-31976D157092), pv 4D075818-755A-4A17-A270-5A55B5D2E483, near LV byte offset = 2260238336.
Nov 12 16:54:03 kernel[0]: disk3: device/channel is not attached.
Nov 12 16:54:03 kernel[0]: CoreStorageGroup::completeIORequest - error 0xe00002e4 detected for LVG "Backup001" (547C5767-6075-4522-8138-31976D157092), pv 4D075818-755A-4A17-A270-5A55B5D2E483, near LV byte offset = 1727528960.
Nov 12 16:54:03 kernel[0]: disk3: media is not present.
Nov 12 16:54:03 kernel[0]: CoreStorageGroup::completeIORequest - error 0xe00002e4 detected for LVG "Backup001" (547C5767-6075-4522-8138-31976D157092), pv 4D075818-755A-4A17-A270-5A55B5D2E483, near LV byte offset = 0.
Nov 12 16:54:03 kernel[0]: disk3: media is not present.
Nov 12 16:54:03 kernel[0]: CoreStorageGroup::completeIORequest - error 0xe00002e4 detected for LVG "Backup001" (547C5767-6075-4522-8138-31976D157092), pv 4D075818-755A-4A17-A270-5A55B5D2E483, near LV byte offset = 4000019382272.
Nov 12 16:54:03 kernel[0]: disk3: media is not present.
Nov 12 16:54:03 kernel[0]: CoreStorage::recover() PV 4D075818-755A-4A17-A270-5A55B5D2E483 from group "Backup001" (547C5767-6075-4522-8138-31976D157092) has been marked missing.
Nov 12 16:54:03 kernel[0]: disk3: memory allocation error.
Nov 12 16:54:03 kernel[0]: CoreStorage: terminating group "Backup001" (547C5767-6075-4522-8138-31976D157092) is BUSY
Nov 12 16:54:03 com.apple.kextd[21]: LVG changed
Nov 12 16:54:03 diskarbitrationd[30]: unable to repair /dev/disk3 (status code 0x00000008).
Nov 12 16:54:03 diskarbitrationd[30]: unable to mount /dev/disk3 (status code 0x00000001).
Notes:
No WD/Seagate software EVER installed.
This drive is used as a TM backup drive only.
This is the 3rd time OSX has corrupted the partition on this drive.
To delete the parition, I have to boot into Linux to delete it. Then OSX's Disk Utility is able to create a new partition (yes, I could have created a partition under Linux).
Oddly enough, I have a 2TB WD FW800 drive in the same FW chain, no problems at all.