It was the first so-called "second generation" EMD diesel locomotive, and was produced in response to increased competition by a new entrant, General Electric'sU25B, which was released roughly at the same time as the GP30. The GP30 is easily recognizable due to its high profile and stepped cab roof, unique among American locomotives.[3] A number are still in service today in original or rebuilt form.
^Electro-Motive Division (1963). Diesel locomotive operating manual for model GP30. La Grange, Illinois: General Motors.