Some cars, rebuilt in 1964–1965 and christened "Blueliners", remained in service with Conrail and later the SEPTA until 1990.

Bethlehem Steel produced a total of 100 cars composed of three types: coaches, baggage-coaches, and baggage-coach-RPO.

[1] Power was supplied via overhead lines to two traction motors built by either Westinghouse or General Electric (GE).

The primary difference was that they carried four traction motors instead of two and could develop 1,100 horsepower (820.3 kW).

The presence of PCBs in the transformers led to the premature retirement of the ACF cars in lieu of a rebuild.

[6] To protect this service the Reading ordered 89 electric multiple units from Bethlehem Steel: 61 coaches, seven baggage-coaches, and two baggage-coach-RPOs.

[6] For this service the Reading ordered 30 additional cars from Bethlehem Steel, identical to the first batch: 28 coaches and two baggage-coaches.

[7] Following World War II Reading bought eight more coaches, this time from American Car and Foundry.