Has an AFL game ever ended 55-48?
Exactly once. On July 13, 1991, Adelaide beat Carlton 55-48, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 55-48 in league history.
That makes 55-48 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 56-48 has happened 2 times and 55-49 has happened 5 times.