 Concurrently with the introduction of the 710, EMD's control systems on locomotives changed to microprocessors, with computer-controlled wheel slip prevention, among other systems.EMD's North American market share dropped below that of its main competitor General Electric in 1987.After the Canada-U.S. Free Trade Agreement came into effect in 1989, EMD decided to consolidate all locomotive production at the Diesel Division of General Motors of Canada (formerly GMD) plant in London, Ontario, a development which ended locomotive production at the La Grange, Illinois plant in 1991, although the Illinois facility continued to produce engines and generators.