The phrase consensus of opinion, which is not actually redundant (see sense 1a; the sense that takes the phrase is slightly older), has been so often claimed to be a redundancy that many writers avoid it. You are safe in using consensus alone when it is clear you mean consensus of opinion, and most writers in fact do so.
Examples of CONSENSUS
Everyone on the council seems to understand the need for consensus.
There is a lack of consensus among the citizens.
The decision was made by consensus.
Yet despite this and other dust-ups during the convention, the general consensus is that Episcopalians weathered this one with their customary civility intact. —Antonio Ramirez, Commonweal, 12 Sept. 1997
Despite years of debate over the best wine to serve at Thanksgiving, no real consensus has emerged. —Harvey Steiman, Wine Spectator, 30 Nov. 1995
Beyond the general goal of sustainability, there was little consensus at the conference on how to get from here to there. —Constance Holden, Science, 6 July 1990
… it is the consensus of opinion that the Iceni in their geographic isolation remained ‘Celtic’ … —Antonia Fraser, The Warrior Queens, 1988