DETROIT — Bob Lutz, the longtime auto industry executive who led nearly a complete overhaul of General Motors' lineup, will retire May 1.

Lutz, 78, confirmed his retirement in an e-mail to The Associated Press on Wednesday.

Lutz, GM's vice chairman and a former U.S. Marine aviator who once crashed his personal helicopter at a Michigan airport, has been responsible for overhauling design at the automaker. He has called the Chevrolet Volt, the gas-electric sedan that can go up to 40 miles on battery-power alone, his proudest achievement.

Lutz is also credited with leading crosstown rival Chrysler to great success in the 1990s.

Lutz acquired a reputation for candor and flamboyance. Long a fan of high-horsepower V-8 muscle cars, he was in charge in 2008 when GM rolled out the Corvette ZR1, which has a supercharged 638-horsepower V-8 engine and a top speed of 205 miles per hour.