Based on my search, I think I'm risking getting flamed, but I thought I might post this. Note I'm using the term "firmware" to describe the files that WD, Dell, and other OEMs refer to as firmware.

I had 1 WD1002FBYS-02A6B0 FW 03.00C06, 1 WD1001FALS-00J7B0, and 3 WD1001FALS-00K1B0 (the FALS drives were all at 05.00K05). As I'm sure all of you are aware, WD rarely ever releases its firmware.

I did however notice that Dell has firmware for various enterprise drives in its FTP (possibly even consumer drives, but I couldn't find them since the file names are obscure). In the MD3000/MD3000i package (MD3000_MD3000i-HDD_FW_A12_R310916.zip) there are a ton of FW updates for various HDDs, including the 0C12 firmware for the RE3 series drives. The firmware is stored as a ".df" file. Looking at this as a hex editor, it's basically just the normal bin file with a header attached. Stripping the first 0x113 bytes gets you the firmware file alone (first 4 bytes of the resulting file should be 52 4F 59 4C).

So first I tried flashing my actual RE3 drive. I used hdparm with the --fwdownload switch (along with the other ones it makes you type). Few minutes later, the flash reports as done. I test the drive, everything works, and it reports as FW version 03.00C12; success! I then tried with the 00J7B0 caviar black. Same story; flash succeeeded, data still intact and readable, and FW reports as 03.00C12. For both of these drives, the TLER settings got set to 8s for read and write (I think I had them at 7s just read before). The power on count also got reset to 0 after the flash

The other drives however are another story. Using the same method, the flash goes all the way through, and then at the very end it says "FAILED: Input/Output Error." The drive still starts up, but it seems like nothing changed. Reports as FW 05.00K05, and the TLER settings remained the same. Disappointing, but atleast the drive didn't die and the data is intact (before anyone asks, yes I did back everything up before going on this adventure).

Looking at the drives themselves, they all look very similar physically. But then I noticed that the 00K1B0 drives have PCB Revision "P1", while the other 2 drives both had PCB "R1" - I'm not sure what the difference is; I didn't spot any obvious circuitry difference. There do exist RE3 drives with the P1 PCB too. And since most (all?) of the firmware is stored on the platters, I'm not really sure that matters. It seems like there's either some kind of write protection, or it's simply writing the firmware to the wrong location.

If anyone has any suggestions about how to go about flashing the firmware on the rest of the drives, I'm all ears. The drives work fine and are TLER capable so I'm not desperate (I'd prefer to use a software-only method. If expensive tools are required, I'll just leave them as is), but it would be nice if I can get all 5 to match