I have 4 drives in my setup. 1 4tb drive is parity. The other 3 are also 4tb drives. I only have user shares setup at the moment. All the data is on Disk 1, which is giving me a bunch of SMART errors. I want to remove it and check it out, but it has the data. When I setup the user shares I had the wrong split level selected. (it is now coreected for new data)  How can I move the data off of that drive on to the other 2 drives? I have been reading somethings about midnight commander, but also with disk shares. Any help or points in the right directions would be great. Thanks!

Unbalance Plugin should do what you want.

so.....using that now......its showing about 36hr to move the 4TB....whoa!

 

You can run most tests on unRAID, or you could just remove the disk and let unRAID emulate it while you decide if it should be replaced or not, posting the diagnostics may also help us to give better advice.