It is a rebuilt WDM2. It belonged to GOC shed earlier. While the MG in SR was being converted, GOC recycled several of it's YDM locos this way. They used the power packs from YDM locos and put them on Broad gauge trucks, occasionally using WDM2 shells to build shunters. The WDM5 is also a similar class that uses YDM4 power packs on a WDM frame and shell.