Speaking with Forbes, Bay also says the movie takes place four years after the last.
"We’re going to start off smaller. There’s a brand new cast," Bay said. "To freshen the franchise we’ve redesigned everything from top to bottom. The history of the first three movies is still there, we start four years later and there’s a reason why we’re meeting a new cast."
Bay continued with mention that Mark Wahlberg is excited and also once again reiterates it's not a reboot when asked.
"No, that’s wrong. We keep the Transformers the way they were, it’s just four years later. There’s a reason the Transformers are redesigned. We’re trying to broaden the franchise and give it more," he said.
Transformers 4 starts shooting next spring and has a July 4, 2014 release also starring Jack Reynor.