GP9rm Diesel Locomotive

Prototype Information

In the early 1980s, CN embarked on a rebuild program in their Pointe Ste. Charles shops to extend the operating lives of the GP9s. The “GP9RM” was the result, which was divided into three groups: The 4000/4100 series were rebuilt as road units, the 7000 series as switchers and the 7200/200 series as “mother” and “slug” pairs. The slugs lacked a prime mover, instead drawing power from the mother to operate the traction motors. The long hoods were cut down and ballast was added to help weigh them down.

The GP9RM fleet included a chopped short hood, addition of three coloured marker lights on both ends, the bell moved to the side of the hood and the dynamic brake blister converted to intake filters. Internally, the units had upgraded 16-645C prime movers and improved electrical systems. The 4000/4100 series road units were changed to have the short hood end designated as the front, with the control stand reoriented, while the 7000/7200 switchers retained the long hood designated as the front. As with any rebuild project, there were differences from one loco to the next as well as minor changes over the ten year rebuild program. One could see these locos all across the CN North American system.