I endorse Dr Frank Mobb's statement that the Second Vatican Council was not infallible. This position is supported by both popes involved at that Council.
Pope John XXIII described the role of Vatican II as the exercise 'of a Magisterium predominantly pastoral in character'. In his opening speech on 11 October 1962, he stated, 'There will be no infallible definitions. All that was done by former councils. That is enough' (Abbott, p. 712).
In his closing speech to the Council on 7 December 1965, as well as at his General Audience on 12 January 1966, Pope Paul VI said, 'In view of the pastoral nature of the Council, it avoided any extraordinary statements of dogmas endowed with the note of infallibility'.
In 1988, Cardinal Joseph Ratzinger (now Benedict XVI), in an address to the bishops of Chile said, 'The truth is that [Vatican II] defined no dogma at all and deliberately chose to remain on a modest level, as a merely pastoral Council; and yet many treat it as though it had made itself into a sort of super dogma'.
Central Coast, NSW