U-joint vs pot coupler

ive rebuilt 4 manual steering boxes
the 3 off pot coupler cars had complete, but in some cases slightly worn upper caged bearings for the worm screw.
the one off a U jointed car had an upper bearing where the cage was in 2 bits and 2 of the ball bearings were flat spotted, the bearing surface on the worm screw showed damage and had a patch like the surface of the moon. luckily the balls can't escape unless you allow the top plug to come undone.

no idea what happend to that box. case was good and showed no sign of hitting anything around the sector snout, and action that would flex it on its mounting and take it out of parralel with the steering column .

none of these cars had any other modifications so flex between front chasis and the solidly bolted steering column would have existed.

not enough to make a proper opinion but it did kinda put me off the U joint set up, even though i can't hand on heart say it was responsible.

Dave