[Pockets69]

UPDATE: Better downgrade here for 3.55 to 3.41/3.15

Sup folks, it seems like the 3.55 firmware downgrader has been released (3.55 to 3.41), we reported previously that kakarot was working on a method to downgrade using a PUP file, but decided not to release it because it only worked in one machine, but now there is hope for you 3.55 users the downgrader has been released.

To quote:

We can confirm, that a successful 3.55 downgrade has now been released. We previously reported on KaKaRoTo's attempt to provide a 3.55 downgrade method. However, the inability to reproduce his results, ended up roadblocking his work. This time around, solidpsycho, of PSX-Scene is claiming to be successful. He released a modified 3.41 PUP which we have personally tested, and can confirm its legitimacey.

NOW ONTO THE BAD NEWS

There are reports of this bricking Slim consoles, do not attempt to downgrade a Slim console with this method. Older Fat PS3's are reporting no issues. Also, after downgrading with this method, your PS3 will think its a 3.56 console. It is recommended that you downgrade the traditional way afterward to 3.15 firmware, and then upgrade the traditional way to 3.41 official firmware.

Here is the PUP: http://www.multiupload.com/2LB3F1NRMK

The lv2diag.self for 3.55 is required but will not be included in download (as its illegal), but google is your friend. It's still a bit "sticky" at the moment but proceed at your OWN RISK. Let us know your results via reply below. A video demonstrating the downgrade can be found below:
YouTube - ‪PSGroove.com - Successfully Downgrading a 3.55 PS3 to 3.41 Firmware‬‏

[VIA PSGroove VIA PSX-Scene]

DO NOT ATTEMPT THIS WITH SLIM MACHINES

DO NOT ATTEMPT THIS WITH SLIM MACHINES

DO NOT ATTEMPT THIS WITH SLIM MACHINES

DO NOT ATTEMPT THIS WITH SLIM MACHINES

A thanks to Mathieulh, for enabling these guys progress as they did.