DETROIT (Reuters) - General Motors' (GM.N) vice chairman and product chief Bob Lutz will retire at the end of this year, ending a legendary automotive career that spanned 46 years and included top jobs at all three Detroit carmakers.

Lutz, 76, will transition to a new role effective April 1, as vice chairman and senior adviser -- providing input into GM's global design and key product initiatives -- until his retirement at the end of 2009, the automaker said on Monday.

Tom Stephens, currently GM's executive vice president of global powertrain and quality, will take over product development at GM.

Lutz was widely credited for the success of GM's more recent products, including the Chevy Malibu sedan and was the leading proponent for its Chevy Volt, an electric vehicle with a small, range-extending gasoline engine.

But at the same time, Lutz remained a controversial and outspoken figure, recently telling a group of journalists that global warming was a "crock of s---."

A former U.S. Marine fighter pilot, Lutz began his automotive career in 1963 at GM. He then went on to work for BMW in Europe, served on Ford's (F.N) board and spent 12 years at Chrysler before rejoining GM in 2001.

A consummate showman, Lutz was famed in Detroit for flying his own helicopter and a collection of aircraft, sometimes to corporate events.

"Bob Lutz was already a legendary automotive product guy when he rejoined GM in 2001," GM Chief Executive Rick Wagoner said in a statement.