SSJ4 is apart of Dragon Ball GT. GT was not in the manga and Akira Toriama didn't create it. SSJ4 was just made to be an excuse for Goku to be in his adult form again. SSJ4, Golden Ozaru/Great Apes, Baby, Black Star Dragon Balls, they are all non canon and fake. With Dragon Ball Super, Resurrection of F, Battle of Gods, Super Saiyan God, and Super Saiyan God Super Saiyan, this all proves GT is officially non canon, since this is all what really happens. GT is not canon, but the new stuff is canon.