Jerry.....try holding the tub assembly still while its agitating and see if the noise stops.....these usually get a sqweek from the snubbers underneath, with that constant back and forth motion, it just wears a mark....
nothing really wrong with it.....just annoying.....and you can't grease it!...
actually I have put a drop of oil on these, but will cause the whole assembly to agitate....but stops with the addition of a foam wrap around the outter tub, helps keep it still, and reduces noise drastically...just a thought!