DETROIT, Michigan - 'Transformers 4' is being filmed in downtrodden Detroit and again a Chevrolet Camaro SS is 'Bumblebee' - but this time, the Detroit News says, it will be a retro model...General Motors and its Chevrolet brand are again working with 'Transformers' but, the DetNews says, director Michael Bay has hinted on his website that the iconic “Bumblebee” may be going retro with a "significantly modified' 1967 Camaro - take a look again at the image above - and that's another huge marketing coup for GM.Chevy spokesman Monte Doran told the Det News: “Camaro played a role in the three previous movies and we’re excited to hear that it will play a part in the fourth.”THIRD TIME AROUNDThe Det News reports that Bay has also released a photo of a green, seventh-generation Chevy Corvette Stingray which, he said, was race-inspired and based on the all-new 2014 production Corvette Stingray soon to be in showrooms worldwide.Doran also told the DetNews: “Chevrolet has been happy to support Bay and ‘Transformers’ producers. We’re looking forward to being part of the fourth instalment."“Transformers 4” is being filmed in Detroit - the third episode to use the dilapidated Motor City, supported, the DetNews reports, by a $20-million incentive from the state of Michigan. The film will apparently spend the equivalent of around R800-million in the state and create 368 temporary jobs.Chevrolet wasn't slow to capitalise on the movies. The Detroit automaker produced a 2012 Transformers Special Edition Camaro in “Bumblebee” yellow; other vehicles from parent were featured in the first “Transformers” for more than 13 minutes.