PARIS/DETROIT, May 22 (Reuters) - Ford Motor Co is expected to announce the departure of Chief Executive Mark Fields in a broad management shake-up, a company source said - a move that reflects growing investor unease over the company's stock market performance and outlook. Forbes and the New York Times reported that James Hackett, 62 and chairman of the Ford unit that works on autonomous vehicles, would take the helm. Ford shares are down nearly 40 percent since Fields, 56, took over three years ago, at the peak of the U.S. auto industry's recovery.