The Via Rail FP9ARM was a re-manufactured version of a GMD FP9A diesel passenger locomotive, rebuilt between 1983 and 1985 by Canadian National Railways at their Pointe St-Charles shops.

While an order for GMD F40PHs was expected to be announced, Via needed to something in the interim to improve service on its routes.

As part of the re-manufacturing many original components were replaced or upgraded - the original 16-567C engines were rebuilt with 645E series power assemblies, and the Woodward governor was revised, thereby raising the net power for traction from 1,750 to 1,800 hp (1,300 to 1,340 kW).

It was felt that many of the FP9ARMs were still usable, and some of the units had their steam generators and associated piping removed and were retrofitted with head end power alternators.

All units were retired and stricken from the active roster upon the completion of delivery of the 900-series P42DCs in late 2001.