Check this out Output Yoke

When I bought my Truck the seal was leaking. Had it replaced. At least 2 yrs. later. the nut came loose, just like that one. Luckily I felt a vibration. Surprised when I saw it so loose. Lucky I didn’t lose the drive shaft. I have a good feel for any amount of slack in my drivetrain. I’m surprised at how little the vibration was. I could barely feel it. Re used the nut, had it hammered on with a 1” gun. 11 yrs later still good.

 

On my old K100, had a similar problem, I didn’t know at the time your not supposed to use the same lock not. Anyways I got into a habit even though I replaced with a new lock nut, I would used the green or blue loctite(can’t remember which one)then button up tight.

 

Whenever I feel the slightest vibration, I’m out and underneath looking for something loose. I pull different trailers, 10 times out of 10, it’s usually the trailers, they all seem to give you a different ride. Also how there loaded. But it’s cheap insurance to always take a look around period, just a habit with me.

 

Me and dad would be under his truck every weekend checking things over. I'd be willing to bet you could count the number of days he missed due to breakdown over 15 years on 1 hand. Take care of your iron and it'll take care of you.

 

Looks to me in that video that it’s not even the right yoke. It appears they ran out of threads before the yoke tightened against the stuff behind it…or maybe the thread are wallowed off but I doubt it.