The EMD G16 is a diesel locomotive built by General Motors in the US and under licence by Clyde Engineering in Australia and MACOSA in Spain.

The Victorian Railways bought six G16C locomotives locally built by Clyde Engineering, known as the X class.

The first eleven were introduced in 1962 and numbered 601–641, and the remaining thirty locomotives were imported in 1964–66.

Thirty-seven locomotives still operate trains on the Vitória a Minas Railroad.

[4] All have now been withdrawn from service but 163 (formerly ER 3361) is preserved at the Israel Railway Museum.

A total of 24 G16 units were built by EMD for the N de M, all equipped with dynamic brakes and introduced between August 1958 and July 1960, their running numbers being 7300 to 7323.

Mexican railroaders nicknamed this locomotive as "Tlaconete", referring to the imperial salamander; it was the first engine that was painted in the olive green, red and white scheme that was kept until 1987.

Ten of the units were built at General Motors factory in the US and were single cabin machines, identical to a standard G16 with the exception of having Iberian gauge 1,668 mm (5 ft 5+21⁄32 in) wheelsets.

In Serbia, Bosnia and Herzegovina, North Macedonia and Slovenia have all kept the JŽ-era designation series 661.

Locomotive 661-203 began a rebuilding program in 2008, undertaken by TŽV Gredelj (Croatia) in association with Electro-Motive Diesel; the bogies and traction motors were retained, but with a new frame and engine (EMD 8-710G3A).