Pro-actively replaceing the hard drives

[dencart2]

I have a CS-WX2 4 TB Network drive that I have used for the past four or 5 years, flawlessly. It has been a great device.

I know my history with HDD's has been that when they go, they go, with little or no warning.

Since these hard drives are near 5 years old, I should be aware of the fact and see about replacing the drives.

Where may I find instruction for replacing the drives? When I search in the Knowledge base for replacing the hard drives, I get nothing back.

Should I format the new drives before putting them in the units? If so, what format? Should I use a backup program to do this and what is the best way to do that?

I would just like some form of instruction for replacing the drives before I get into it and possible lose my data in an innocent transfer error.