GM Provided 67 Vehicles for Transformers 2

In an article with USA Today, Bay and GM briefly discussed the relationship between the two as GM provided the production with 67 cars total that was a combination of prototype, concept and real cars.

"They were responsible for building the cars, and I was trying to get my check because we built the cars, fronted them the money, and they were late on paying us," Bay says. "I was like, 'We better get our check fast before they go bankrupt.'

Chevy won't reveal what it cost to provide cars, but spokesman Steve Janisse says 67 vehicles were used, and 52 of those were "non-salable," specially built prototypes used for testing, engineering and display.

While participating in a movie may seem counterintuitive given GM's hardships, the company says Transformers could be a big help. "Although we've significantly reduced spending around all promotions, and in this case we did not pay any placement fee, we still need to market and sell cars and trucks," Janisse says. "We know this is a good investment — that it interests people in Chevrolet and ultimately drives people to check out our vehicles."

Most of the 22,000 2010 Camaros put on the market last month were pre-sold, Janisse adds, with interest fueled by the design's use as Bumblebee in the 2007 film.

Bay says the cars themselves become like celebrities, something he witnessed while shooting in a remote part of the Middle East. "The money they spend is pennies for the amount of goodwill. Bumblebee is one of the most famous cars in the world," the director says. "Literally, we're in this poor little town in Jordan, and all these kids surrounded (the car). They all knew Bumblebee's name."