Checked the oil level in your differential?
Phasing is discussed after 2:00.
Sure. It has the effect of accelerating and decelerating each component in every revolution, working against one another.
Then that makes it a likely suspect.
I would either trying adjusting the shoes as per FSM, and/or pull the drum and take a look-see.
Unlikely, I'd say. I'd expect a bad bearing make a more or less constant sound, possibly changing note with turns left or right.
It would be completely destroyed before you would noticed it in the handling, if ever.
Yeah, me too.
There are various military types available for the front, you could look at those.
After seeing your video, I agree it is apparently a fuel issue.
Since this problem appeared right after you "cleaned" the carb, I'd say...
Well, that is important information, which I don't think we had before.
Is it possible you have a vacuum leak? Carb gasket?
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