I know with the manual hubs you dont stuff them with too much grease as they stick and jam. I had that happen and had to tear then apart. I wouldn't be surprised if too much grease on auto hubs would also be a no no.

88 Montero, StarQuest turbo, Kormex 5speed +tuff-pan w/phoenix f. stage2 clutch, 4in lift+33' tires, 4.875 lsd, short-throw shifter, Aisin hubs, SR big brakes, gen2 uca's, elantra alt, and so much more... 16g turbo w/hardpipes + 4.90 locking disk-brake axle soon (maybe lsd or aussie front??)