Contract talks between the United Auto Workers union and General Motors began in Detroit on Monday with the traditional handshake ceremony.
A similar event at Ford is scheduled for Monday afternoon in Dearborn.
Talks with Chrysler began on Friday ahead of the ending of the current national contract between all three US-based car makers and the UAW on 14 September.
Wage reductions, healthcare and retiree benefits are all on the agenda as the domestic Big Three battle to compete with Asian-owned rivals whose US plants are mostly non-union and have far fewer retirees.
Analysts told the Associated Press that Ford is likely to ask for deeper concessions than its two US rivals, perhaps even temporary wage cuts.

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By GlobalDataAll three have said they need labour cost parity with the Japanese, who make about $US2,000 per car more in profits. Detroit automakers claim their hourly labour costs are about $25 higher than the major Japanese firms when those healthcare, retiree and other costs are factored in, AP added.