I have seen posts where the bushing runs hot for a while. I wonder if the spline problem was the cause.
There are three possible reasons why the bushing gets
HOT 1.Scored bushing
2.Bushing lacked prelube.
After Okie bushing is installed, gear lube should be squirted down the torque tube, before sliding the rear yoke onto the propeller shaft splines.
It takes awhile for the transmission to funnel gear lube into the u-joint ball housing, then to the rear yoke and propeller shaft bushings.
3.Failure to replenish gear lube in u-joint ball housing.
Also the original oil seals were leather, and less prone to damage.
The oil seals used today are neoprene and can be cut easily from the raised spline burrs.
Now you have a brand new oil seal leaking gear lube into the rear end.
When the rear end fills up with gear lube, it flows out into the brakes.
Then you can't stop.