2011 New York Auto Show: Big fear is $5 a gallon gas

2011 New York Auto Show reveals growing concern about rising gas prices. Executives at the 2011 New York Auto Show say sales could fall by 2 million vehicles a year if gas reaches $5 a gallon.

By Phil LeBeau, CNBC Correspondent

Walk around the 2011 New York Auto Show and you'll hear auto executives pondering the million dollar question: What happens if gas hits $5 a gallon?

A year ago you would have scoffed at the possibility. Not anymore. And among auto executives there's a growing concern that when gas hits $4.50 a gallon sales will dramatically shift to smaller, more fuel efficient cars.

But if it ever hits $5 a gallon, auto insiders fear sales of all vehicles will slow down. It's a psychological barrier that could spook people into saying, 'I think I'll hold off buying a new car, truck or SUV.'

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Does that mean sales will come to a screeching halt? No. But more than one exec predicted we could see sales slump down to a pace of 11.5 or 11 million vehicles. That would be troubling in a year when sales are expected to come in between 13 and 13.5 million.

Already, automakers are shifting their production to more fuel efficient models. And fortunately, demand remains robust. But deep in the hearts of many an auto executive there's a fear of $5 a gallon gas.