Mike Siegrest, a 35-year General Motors veteran, briefly worked on the failed Oldsmobile diesel V-8 from the 1980s. Now, he and his team are equipping GM's first diesel car since that decade: the 2014 Chevy Cruze diesel. It arrives in showrooms in June. As Chevy plans to challenge longtime diesel leader Volkswagen, it will need to convince U.S. consumers that the smoky, smelly diesels of the past are long gone. Siegrist was interviewed at GM's powertrain facility in suburban Detroit in May.