The morning Zephyr has a trio of P42DCs, all elephant style, leading it up this morning. It is not entirely clear why the extra unit is on the train, but it usually for one of two reasons.
1) The unit was added somewhere along the route due to a mechanical issue with one of the two units originally on the train.
2) One of the units is being sent to California for use on the west coast, quite possibly the Coast Starlight.
Today, reason #2 is most likely the reason for the extra unit today.
