Hey there, cphillips.
Sorry to hear about the issues you're having with the drive. Check what's the reported capacity of this HDD in BIOS. Having in mind you want to format it, I assume there's no data on it which you want to save, so I'd recommend that you download DLG (Data Lifeguard Diagnostics) and try to Write Zeros on it. This is basically a low level format. After you've done that, the drive would have to be initialized, partition and formatted as if it was a brand new internal HDD. Here's how to do it:
How to low level format or write zeros (full erase) to a WD hard drive or Solid State drive. If that doesn't help, I'd recommend that you test the drive with the same tool:
How to test a drive for problems using Data Lifeguard Diagnostics for Windows, to see what's the situation with it.
Hope that helps. Please let me know how everything goes.
Boogieman_WD