Ford will invest $1.3 billion to expand its plant in northern Chihuahua state, where it will build two new diesel engines, with another $1.2 billion planned for a transmission plant in central Guanajuato state, the sources said on Tuesday. The U.S. automaker will announce the investment in Mexico City on Friday to celebrate the 90th anniversary of its presence in Mexico. President Enrique Pena Nieto will attend the event. Ford is Mexico’s fourth-largest auto exporter, according to official industry figures, selling 108,417 units abroad during the first quarter.