The EMD G22 Locomotive Series made their debut in 1967 after the rise in popularity of the export EMD G12. Designed to meet most First World, Second World and Third World country requirements, the G22 Series was equipped with a naturally aspiratedEMD 645 Series engine as well as four axle Flexicoil Type-B trucks which carried a low per-axle weight. Based on customer input, the G22 Series was defined by various designations that suited the customer's railway operations.
The standard suffixes applied after the G22 designation were if the customer purchased locomotives with specific traction motors to fit Narrow Gauge (U) or Broad Gauge (W) rails. As the years progressed, the customers began to have more options available for their locomotives including EMD Dash 2 electronics, alternators instead of generators, A1A-A1A running gear and/or steam generators.
The G22 designation could be freely applied to the designs of any EMD export model or a licensee of EMD as long as the electrical and mechanical gear were left unaltered.