Automotive Executive. He led General Motors Corp. through a booming period of the 1970s as chairman and CEO from 1974 to 1981, when the automaker accounted for well over half of all cars and trucks sold in the United States. GM had become so powerful, the U.S. government was keeping an eye on the company as a possible monopoly that needed to be broken up. A tall, reserved executive, he was the stable, dignified head of the company. He was known for his character. He was former chairman of the Business Roundtable, an association of top U.S. CEOs, a director of the University of Illinois Foundation, a director of the United Negro College Fund and a member of the board of overseers of the Memorial Sloan-Kettering Cancer Center in New York. He was born in Hornell, N.Y., in 1915 but moved with his family to Chicago in his youth. After graduating from the University of Illinois with an accounting degree, he joined GM in 1938 as a clerk on the comptroller's staff. He served in the U.S. Navy from 1943 to 1946. He took the helm of GM in 1974 in the midst of an oil crisis. U.S. customers were starting to demand smaller, fuel-efficient cars, but the impact of the Japanese imports had yet to take hold. During his tenure as chairman and CEO, GM reached a sales record in the United States of 7.1 million cars and trucks in 1978. After his retirement on Jan. 1, 1981, he continued to serve as a member of the board of directors until May 1988. A man considered by most of the highest integrity, he died of natural causes in Boynton Beach, Fla. He is survived by his wife of nearly 65 years, Catherine Rita (Sis) Murphy, daughters Catherine A. Murphy and Maureen M. Fay, son Thomas A. Murphy Jr., eight grandchildren and 10 great-grandchildren.