Fiat boss Sergio Marchionne has now headed west to Detroit ahead of next week's show and also ahead of a pretty crucial referendum among its workforce - and a potential union split.

The Italian automaker's 5,500-strong Mirafiori staff - whose unions' protracted negations have rivalled even those at Pomigliano d'Arco - are due to vote next Thursday (13 January) and Friday on the future of their plant.

But FIOM's position ahead of the vote remains vague. "Nobody at FIOM is recommending yes," a union spokesman in Italy told just-auto, although it is permitting its members a free conscience. "The question is how to behave before the referendum and after if the 'yes' wins," added FIOM.

Does that mean the union is seeking to establish a position that admits a 'yes' vote will be possible and is it tacitly accepting Marchionne will have his way?

And despite telling just-auto yesterday that Fiat was seeking a a substantial majority, the manufacturer today said it would take 51%, before qualifying this with: "It needs to be at least 51%."

However, although FIOM is allowing that its members are free to vote, the real battle may be an internal one as the labour body meets its parent CGIL in Rome this Sunday to establish a common position ahead of the vote. 

"The question is how to behave before the referendum and after if the 'yes' will win," added FIOM.

So there appear to be two strong issues, namely FIOM's reluctant acceptance the Mirafiori workforce will vote in favour, but also that it may be facing an internal battle within its ranks and parent organisation CGIL.

Because as well as Sunday's referendum meeting, CGIL and FIOM are also scheduled to get together on 15 January - a Saturday of all days - to discuss the vote's outcome from the previous evening.

"Maybe on 15 January, there will be a clash between the two political lines within CGIL and FIOM," said the FIOM spokesman.

Marchionne will be watching keenly from afar should any potential split within the hitherto solid union front occur.

Are cracks beginning to show?