Freshened Chevrolet and GMC pickup trucks will be framed once again by Cosma.

After toying with the idea of using a unibody for the next iteration of its pickup trucks to improve fuel economy, General Motors Company has decreed the next full-size pickups will continue to be built on a full frame.

Magna International Inc., one of the world’s largest automotive suppliers, has announced that one of its units, Cosma International, will supply the frames for GM’s full-size light-duty pickups and SUVs. This is the third generation of frames Cosma has been awarded on this platform by GM, Magna announced.

Magna did not disclose the timing of the project, deferring to GM, which doesn’t discuss specific, future product plans. However, its now seems likely the first GM vehicles built off the new frame could roll out in about three years in late 2012 as 2013 or even 2014 models.

Despite new fuel-economy rules, the pickup truck occupies a critical spot in the line of all three domestic manufacturers, and sales of pickup  trucks, because of their broad use in a variety of work settings, are expected to continue to represents 12-15% of new vehicle sales in the U.S.

The new investment also suggests that the threat from Japanese brand trucks has been successfully contained. Senior Toyota executives are already suggesting that they are stepping back from future investments in full-size pickup segment after losing billions of dollars on what turned out to be an ill-conceived frontal assault on well-entrenched entries from Chevrolet, Dodge, Ford and GMC.

Cosma will produce the new frames from its state-of-the-art manufacturing facilities located in St. Thomas, Ontario, and Saltillo, Mexico.

“Receiving this third-generation frame business from GM is a real testament to our ability to deliver on key areas including cost and quality,” said Horst Prelog, President, Cosma International. “GM is a long-term valued customer of ours and we look forward to continuing our partnership with them.”

Cosma manufactures a comprehensive range of metal body systems, components, assemblies and modules including complete vehicle frames, chassis systems and body-in-white systems using a variety of innovative processes, including hydroforming, stamping and roll forming.