PCC cars were introduced to the line in 1947 and 1948, replacing Nearside cars which had operated the route since the teens. The Philadelphia Transportation Company (PTC) attempted to introduce a fleet of 100 PCCs to the line in 1942, but an insufficient power supply for climbing Chestnut Hill caused these cars to be sent to Luzerne Depot to serve other routes instead. After World War II and its materials shortages and restrictions ended, a substation was built at Germantown Avenue and Mermaid Lane, and PTC assigned 85 new PCCs to the line; the difference in number of cars was due to postwar ridership declines.