Shogun Shogun diff issues

[Opua]

Hi everyone, I’m having an issue with my Shogun it’s been a bit of an unlucky run for this model lately. A nasty noise has started coming from one of the differentials. I began by replacing the input gear in the rear differential, but the noise persisted. I then took apart the front differential and replaced both the input gear and the ring gear, yet the noise is still there. I checked the center differential, but nothing appears to be broken. Finally, I disassembled the rear differential again, removed the new input gear I had installed, and replaced it with the input gear and ring gear from the front unit (since I was certain the problem wasn't in the front)but the nasty noise is still there! I’m at a loss as to what to do next! I’d appreciate any advice you might have. I’ve included a link to a short video I uploaded to my channel, where you can clearly hear the unpleasant noise coming from the Shogun.
Excuse for my English but I'm Italian.

 

[KnowAir]

What do the spider gears inside the diffs look like? How smoothly do the diffs spin? No binding?
I had a similar sound that turned out one of the input cups was slipping on the input shaft even though it “felt tight”. I mean the grub screw that locks the cop to the flat portion of the diff input shaft.
There was a bunch ot thread locker in the threads that was preventing the grub from properly holding the cup to the input shaft.

 

[Nelson.81]

That seems similar to what mine was like, I had broken a hinge pin & drivepins had worn down it was spinning in the diff cup, was surprised it still had drive & didn’t spit the dogbone out. Or it could be input drive cup loose & spinning on the shaft.

 

[Opua]

It’s driving me crazy. I’m going to try taking the center differential apart again to re-examine all the gears, including the ring gear; after watching this video, I also checked the pinion and found a broken tooth. I installed a new pinion, but the noise is still there. Could that missing tooth have damaged the ring gear somehow? In your opinion, is this type of noise which occurs when I accelerate coming from the center differential or the rear one?