I'm not sure how significant that is because these warped market shares were caused by the strike that is now over.
I don't think there's any sector- or stock-specific news that is moving these stocks today. The gains you're seeing are a reaction to the steep drop these stocks have taken of late and the recovery the shares have seen for the last few sessions. It's pretty much a group recovery.
I don't think Wall Street had fully realized the dependence of GM's and Ford's North American earnings on a few light-truck models. That was the nasty surprise that drove their shares down.