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PROTOTYPE HISTORY
1600-Series GMD-1A
In 1988 CN rebuilt 15 more GMD-1 locomotives for continued branchline use on the
Prairies. Unlike the 1100s, this was a major rebuild performed by CN’s Pointe St-Charles
shops in Montreal. The batteries were removed from the short hood and replaced with a
chemical toilet and access door; the batts were moved outboard beside the short hood.
The units received anticlimbers, ditch light brackets, improved spark arrestors, straight
exhaust stacks, upgraded sanding, snowplows, improved traction motors, and Wabco
26L brakes (replacing the old 6SL and 26L systems). The cabs were re-oriented to run
short hood forward, and interior facilities were improved – they now had a fridge! The
1600-series units were called GMD-1A and received the class designation GR-612A.
Most importantly for railfans, the 1600-series GMD-1 locomotives received what would
become the definitive GMD-1 paint scheme: red short hood and gorgeous striped long
hood. These were instantly recognizable to railfans from a distance and came to symbol-
ize Canadian branchline traffic in the 1990s.
1400-Series GMD-1B
CN followed the 1600-series rebuilds in 1988 with the 1400-series rebuilds in 1989.
The GMD-1B, classified GR-412B, is mechanically very similar to its 1600-series cousin.
The main differences are the larger, 2000 gallon fuel tank and the 4-wheel, Flexicoil
trucks. The 1400s also received a toilet, accessed from inside the cab. According to one
CN engineer who has operated the GMD-1 locomotives since the dark ages, the addi-
tion of toilets was a reflection of the fact that railroading was no longer a boys-only club.
The women engineers requested toilets in more units. Operation of the 1400s remained
long-hood forward.
1400-1402 were rebuilt from 1917, 1916 and 1913 respectively, thus retaining their
original Flexicoil trucks. The remaining 1400s done in 1989 (numbers 1403-1423)
were rebuilt from 1000-series GMD-1 locomotives using the trucks from retired GP9
engines.
The 1400s and 1600s received upgraded power assemblies, effectively creating a
645C prime mover rather than its original 567C. The 1100s did not receive upgraded
engines.
1400-1437 Series Retrucked 1600s
Between 1998 and 2000, all 15 1600-series GMD-1 locomotives were rebuilt to 1400s
using the trucks and fuel tanks from retired 1100s. Just to add some interest for railfans,
these were numbered 1430-1444.
At the time of writing, many GMD-1 locomotives are still in service today and there is
talk of a further rebuild program.
