Four of the initial class B1 order were delivered ballasted, lower gearing, & with 400 hp/axle so they could be better used for yard and transfer service. They were initially assigned to Albany, Portland, Boston, and New London, but moved around the system as traffic flows varied over the long slow decline of freight traffic in the NE, with the last two only going out of service in 2020.

Number	Disposition
236	Retired 2020, to NMOT 2023
237-238	To class E prototypes #448, #449 1967
239	Remanufactured to class BCC5 2020