Walter Wieland will retire next May as president and managing director of GM do Brasil and will be replaced by Ray Young, a GM North America vice president and chief financial officer who joins from January 1, the company said. Wieland will assist Young with the transition and continue reporting on special assignment to Maureen Kempston Darkes, GM group vice president and president of GM Latin America, Africa and Middle East. Mary Boland, executive director of finance and controller for GM North America, will replace Young on December 1.