On my Dana 44 it IS screwed into the upper ear of main housing. I am not sure exactly what it is supposed to do, if you do not back it off as the directions on ball joint replacement dictate it is nearly impossible to reinstall the knuckle. I don't know if it is there to help facilitate the removal of the knuckle, but I do know if you unscrew it first it is near impossible to remove the knuckle.
Definition of experience ;Ability to recognize your mistakes as you make them again.
Don't ask how I know.
Definition of experience ;Ability to recognize your mistakes as you make them again.
Don't ask how I know.