The Class B motor was the mainstay of PV&T electric freight operations from their delivery until classes J and K were introduced, and still make up a tenth of the PV&T’s electric roster.
Most of the class B motors were rebuilt into BCC, BCC2, BCC3, BCC4, BCC5, and N starting in the 1990s, so are basically new motors.
55 of them are still in service, and can be found everywhere the 3kvdc wire goes.