The EMD G22C Series were first introduced in 1968 to replace the popular G12 along with various improvements. They carry a low per axle weight on their Flexicoil Type-GC trucks and were now the first model series to have a low nose as a standard option as well.
The G22 series now carries a U or W suffix after the model designation to indicate the type of traction motors. A C indicates six-axle C trucks, while a 4 indicates six-axle A1A trucks (only four of them powered); although there never has been an indication of A1A trucks until 1993.
The designations could apply to any kind of export locomotive design of EMD or another licensee of EMD as long as the electrical & mechanical gear was left unaltered.
Overview
With the introduction of the 645 engine for export models in 1967, the model designation numbers changed by adding 10. To meet customer demands of a six axle version of the popular G12, EMD created the GR12 which was slightly longer and taller to accommodate the six axle Type-GC trucks.
Although the orders lacked for the GR12 due to the weight and size of the locomotive, EMD revised and designed the lighter G22 series model to accommodate the Flexicoil Type-C truck and introducing the new EMD 645 series engine. With relocation of the batteries within the carbody and increasing the fuel tank capacity, the G22C series was the same length to that of its four axle counterpart, the G22. Production spanned longer than the four axle G22 version, but with smaller orders.
Several models were introduced:
G22CW
G22CU
G22CU-2
GL22C
GL22C-2
GL22MC
G22CW
The EMD G22CW was first introduced in 1969. Unlike its predecessor GR12, the G22CW carried a CW suffix which indicated that this model had six axles (C) and traction motors that could fit from standard gauge rails to 5 ft 6 in (1,676 mm) gauge rails (W).
The G22CW found most of its popularity in Argentina and Sri Lanka, as the largest order were each placed by them with 15 units.
Production spanned from July 1976 to November 1990
The EMD G22CU first appeared in 1969. Designed mainly for the narrow gauge market, the G22CU carries a CU suffix which indicates that this model has six axles (C) and traction motors that can fit from one meter gauge to 5 ft 6 in gauge rails (U).
The G22CU found most of its popularity in Pakistan, as older locomotives were being replaced.
Production spanned from February 1969 to June 1982.
Beginning on January 1, 1972, export locomotives then had the option to carry EMD Dash 2 electronics, adding the (-2) suffix to the locomotive model. Only Argentina and Taiwan purchased the G22CU-2.
When most second and third world railroads couldn't operate standard EMD Locomotives due to their weight, EMD introduced the L suffix which indicated the locomotive had a lightweight frame. The locomotive designation was changed to GL22C. However, as these locomotives had a much lighter frame, the application of the U or W suffixes no longer applied.