Controversial General Motors Vice Chairman Bob Lutz will retire effective May 1, according to a statement released by the company. Lutz, 78, postponed his retirement in July in order to assist GM as it struggled to emerge from bankruptcy.

Lutz has made a name for himself by paradoxically challenging global warming while serving as the principal champion for the plug-in electric Chevrolet Volt scheduled to debut later this year.

Hired in 2001 by then CEO Rick Wagoner, Lutz revitalized product development at General Motors and has most recently served as senior adviser to current CEO Ed Whitacre.

By his own description, Lutz has served as a "minister without portfolio for generalized advice of counsel." Speaking to reporters in Switzerland he added, "I was kind of the last in the all-new management team. I think I served a role in creating the connectivity to what had been done in the past, what was decided in the past, and why things were decided the way they were, why we did the things we did."

Lutz backed the high-performance, high horsepower Dodge Viper during his previous time at Chrysler, a project in keeping with his former career as a fighter pilot. At GM, however, he set his sights on the Volt, a plug-in electric at the heart of the company's attempts at self-redefinition.