The BMW plant in Spartanburg will undergo yet another expansion - and get the new X4.

The U.S. auto industry continues to be one of the drivers of the American job market – in this case, thanks to German manufacturers BMW and Daimler AG.

The two plan to add more than 1,500 jobs at factories in the Carolinas, the expansion at BMW potentially making its factory in Spartanburg, South Carolina its second-largest.  It is already this country’s largest exporter of automotive products to markets outside of the NAFTA region.

Daimler Trucks North America announced the addition of a second shift and plans to ramp up production at its Freightliner Truck Manufacturing Plant in Cleveland, North Carolina, creating more than 1,100 new jobs by the end of 2012. The additional workers represent a 72% increase in personnel at the plant and will include approximately 1,072 shop employees and an additional 29 engineering and support positions, the company said in statement.

A majority of the positions will be filled with recalled workers who were laid off during the recession in 2009.

(Toyota, Nissan, Hyundai R&D plan hiring binge in Detroit.  Click Here for more.)

The ramp-up will nearly double the daily production rates at the Cleveland plant by October 2012. The increase in production capacity and hiring comes in response to demand growth which has created backorders as long as six months for the Freightliner Cascadia model.

The Cleveland plant currently employs approximately 1,400 shop employees and 72 engineers, managers and support staff. The largest Freightliner Trucks manufacturing plant in the United States, the factory produces Class 8 on-highway truck models, including the Cascadia, Columbia and Argosy product lines. Freightliner trucks also are sold internationally, with nearly 20% of the trucks built at the Cleveland plant sold throughDaimler subsidiaries in Australia, New Zealand and South Africa.

In conjunction with the ramp-up at the Cleveland plant, Daimler also will hire 100 employees at its nearby Components and Logistics Plant in Gastonia, N.C.

Nearly 70% of the vehicles produced at the BMW plant in Spartanburg were exported last year, or 276,065 in all – a 73% increase over 2010.  The increase was driven, in part, by the weakened dollar, which makes it more competitive to produce vehicles in the U.S., especially when compared to products made in Germany, where BMW’s largest factory is still located.

With the 2 millionth car to roll out of the South Carolina plant in background, Frank-Peter Arndt, the BMW Group Board Member responsible for Production,  announced it plans to add 300 jobs at the factory this year. The company plans  to expand its line of Sport-Activity Vehicles by adding the new X4.

“I am delighted to announce today, over the next three years, we plan to invest nearly $900 Million U.S. dollars. With this investment, we will be able to produce 350,000 units here in the mid-term,” said Arndt. “This is one reaction to the rising global demand for our BMW X Models.”

The increase will bring employment at the plant to 7,500 by the end of the year.  BMW says it has so far invested $6 billion in South Carolina since first opening the factory.