[4][5] In October 1958 the Peninsula 400 received bilevel equipment including coaches, a lounge and a parlor car.

This introduction marked the first time a North American passenger train used head end power (HEP) in preference to steam heat.

[12] On January 31, 1949, in Rock, Michigan, the Peninsula 400 had an overheated bearing on a failed traction motor that caused a derailment.

A similar accident happened on January 11 to the Seaboard Coast Line Orange Blossom Special,[13] which also had an overheated bearing on a traction motor on the diesel locomotive, which then seized and caused a derailment.

In both cases the overheated motor froze up, which caused the wheel to stop turning and wear down a flat spot, eventually derailing the trains.