Automotive planners might have been more reluctant if the ongoing recovery in sales wasn't consistently outperforming even the more optimistic forecasts. Demand is expected to remain at the dizzying heights of more than 15 million units for the next few years, and then grow again, according to some estimates.
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LMC Automotive, a Troy, Mich., forecasting firm, predicts that new vehicle volumes will increase to 17 million units in 2017. That level is on par with the late 1990s and early 2000s. The rise will be fueled, in part, by pent-up demand and the need to replace older vehicles. That's likely no surprise considering the average vehicle on U.S. roads is now a record 11.2 years old.
This latest boom means automakers and suppliers are scrambling to find the talent necessary to keep up with the sales wave.
Since the slow automotive recovery began in 2010, Detroit's Big Three makers have hired—re-hired—tens of thousands of employees, both blue- and white-collar. And the figure has increased almost exponentially when foreign-owned makers and industry suppliers are added in, Examples include Volkswagen opening a new plant in Chattanooga, Tenn., and Toyota boosting capacity at a number of its U.S. facilities.
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Through May of this year, automakers and parts suppliers hired 8,000 workers and the rate of hiring is expected to increase with the recent announcements. The Center for Automotive Research expects the industry to add 35,000 over the full year.
Chrysler, Honda, GM, Mercedes-Benz and Ford are adding more than 13,000 people this year.
While companies are looking to add to their rolls at all types of positions, companies have been lamenting their inability to attract engineers for some time now and the need is greater now more than ever.
Engineer was the most difficult job to fill in the Americas in 2012, up from fourth in 2011, according to Manpower Inc.'s 2012 Talent Shortage Survey of 10,232 employers in North and South America. Engineer was the second most difficult job to fill globally, according to the annual survey.
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This only compounds the issue for suppliers. Prior to the urgent need for engineers at the automakers, suppliers were already struggling to attract them.
"As volume goes up, we will really need to add heads," Mel Stephens, a spokesman for Lear., which makes automotive seats, told the Associated Press.
The recent hiring binge is even causing worker shortages in some areas. Skilled workers such as engineers are hard to find, especially in the Detroit area.
"Engineering is a growth field. We don't have enough engineers," said Mark Reynolds of the Society of Manufacturing Engineers. "Manufacturing is also experiencing growth. Jobs are coming back to the country, and to Canada."
Michigan currently has more than 27,000 mechanical engineers, but there is a growing, long-term need for more. The U.S. Department of Labor's Bureau of Labor Statistics projects a 9 percent annual growth rate in the field of mechanical engineering, and that equates to more than 2,400 new jobs in Michigan every year.
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Nearly a quarter of all current mechanical engineers are over 55 years old and soon will be retiring. In addition, emerging technologies in biotechnology, materials science and nanotechnology are expected to create additional job opportunities for mechanical engineers. Michigan needs a new generation of engineers to meet the current and future demand of the state's employers.
In a report on talent sponsored by Deloitte and the Manufacturing Institute, 48 percent of companies nationally said they expect to experience hiring challenges in the next three to five years when recruiting for engineers. Manufacturers all over Michigan are indicating there is a shortage of all types of engineers.
—By CNBC Contributor Paul Eisenstein. Follow him on Twitter