Hi there twisted31,
I would totally agree with weberdarren97.
The first thing you need to do is to back up the data stored on the drive, as the drive could fail at any time.
Most probably, there are some bad sectors on it. Look for pending/reallocated and uncorrectable sectors.
In case it is under warranty, you should be able to RMA it.
Cheers,
D_Know_WD