Bruce, how old was the 4tb hard drive, most now have around 3yrs warranty, not that it helps with data loss though.
Just following on from my post earlier, Macrium reflect free works a treat, if you look at Leo Notenbloom's tutes etc, you should see what I mean. I run it as well as EaseUS Todo backup which costs around $30 aud. They are pretty new, but getting some good reviews as well.
http://www.todo-backup.com/