As part of his quest for a mega merger, Fiat Chrysler Automobiles Chief Executive Sergio Marchionne sent an email to General Motors Co Chief Executive Officer Mary Barra in March suggesting combining the automakers but was rebuffed, the New York Times reported on Saturday. Quoting two people with knowledge of the email, the Times said it detailed how global carmakers needed to consolidate to save money and suggested a merged GM and Fiat Chrysler would cut billions of dollars in costs and create an automotive giant.