New Zealand DG and DH class locomotive

The New Zealand DG and DH classes were forty-two diesel-electric locomotives that ran on New Zealand's rail network between 1955 and 1983. They came from a renegotiated English Electric contract after the DF class proved unreliable, and were a smaller single-cab version of the DF with a similar bulldog nose. English Electric allocated final assembly to its sub-plants, with works numbers 2254 to 2273 assembled at Robert Stephenson and Hawthorns and 2274 to 2295 at the Vulcan Foundry. The South Island locomotives were first classed DH because adjustable bogies let them raise their adhesive weight and tractive effort; in 1968 they were converted to DG standard. Ten were rebuilt between 1978 and 1980, but reliability problems persisted.