The AMWU has welcomed signs that Holden may recommence the second shift as early as October at their manufacturing plant in Elizabeth, SA.

AMWU SA Secretary John Camillo said the workforce has been told the second shift will involve up to 500 jobs.

"What we have been told by Holden is that they are looking at putting on a second shift, a permanent day shift and a permanent afternoon shift, in the last quarter of this year," he said.

The factory currently produces around 340 cars a day, but on two shifts this can increase to a maximum of 620.

Mr Camillo said the proposed boost in staffing was due to better export potential and crucial investment in the vehicle industry by Prime Minister Kevin Rudd and Industry Minister Kim Carr.

“After a decade of inaction by the Howard government, we’ve had real investment in car manufacturing and that investment has been crucial in helping Australian car manufacturers survive the global financial crisis,” Mr Camillo said.

The Federal government has made a commitment to invest $6.2 billion in the vehicle industry over the next thirteen years to help encourage confidence in the vehicle and component industry.

Representatives from Holden have not confirmed when the second shift will be added, but Mr Camillo said Commodore sales have picked up and he believes more shifts are required to build the four-cylinder Holden Cruze.

Mr Camillo said it’s unclear whether workers who took redundancy packages from the Elizabeth plant last year could be re-employed on the second shift. But he says any boost in staffing will have a positive impact on the local economy.

"Morale is very good at Holden because they can see the light at the end of the tunnel," he said.

“If the extra shifts go ahead it means everyone would be on full production and Holden would have to employ more people. It could be up to 500 workers, and that would have a flow-on effect for suppliers as well.”