Sacred infallible Tradition is not an oral tradition. If it were, then one could quote an infallible sentence or paragraph from such an oral tradition. If it were, then one could write down the oral tradition and we would have a second Bible (which is not possible).
Tradition is ‘the deeds wrought by God in the history of salvation’ (Dei Verbum, n. 2). The deeds of God themselves are Tradition itself.
The transmission of Tradition is accomplished with the spoken and written word, but moreover with the deeds of the faithful imitating Christ, and in the spiritual life of the Church. Now the spoken and written words of the faithful are not infallible, nor are their deeds, therefore such things are merely the means of transmission of Tradition, and not infallible Tradition itself.
Just as Scripture is transmitted by various editions of the Bible that can contain errors particular to that edition, so also it Tradition transmitted by individual Christians who can make mistakes, but in so far as the do imitate Christ, they help to transmit Tradition.
Ron