The EMC E4 was a 2,000 horsepower (1,500 kW), A1A-A1A passenger train-hauling diesel locomotive built by the Electro-Motive Corporation of La Grange, Illinois.

The E4 was the fifth model in a long line of passenger diesels of similar design known as EMD E-units.

The front noses of the EA, E1A, E3A, E4A, E5A, and E6A cab units had a pronounced slant when viewed from the side.

Later E-unit models received the same blunted "bulldog nose" as the F-units.

Both models were identical, save for the E4 having a pneumatically-operated nose door passageway in order to facilitate crew movement between units in a locomotive consist.