iMac late 2012 1TB Fusion - Replace hard drive

[PatrickNSF]

After searching the threads for a while, I'm having trouble finding any info on replacing the 1TB hard drive component of a Fusion drive with a 4TB hard drive and creating a new Fusion drive. I'm comfortable disassembling the iMac with the iFixit guide, and not concerned with warranty issues, but having trouble figuring out what's involved once I swap the drive to reformat as a new 4TB Fusion.

Any leads would be appreciated.

 

[Eriamjh1138@DAN]

There are many guides on DIY fusion drives. I just did one on my 2011 MBP.

The most important is a backup before you do anything.

Otherwise, it's:
Remove HDD
Replace HDD
Create fusion drive across SSD and new HDD
Reinstall mavericks (if necc.)
Install backup

You have to pay attention to your recovery volume but I don't know the details. There's threads about that. Just test with CMD-R after reinstalling to see if it works.