The group was protesting for better enforcement of safety protocols and equal pay for some factory workers hired on lower salaries offered as part of a tiered system implemented as the auto industry struggled.

"That's all we would really like in this contract, equal work for equal pay," said Melvin Thompson, former president of the UAW Local 140, who was protesting with about 25 others. "I don't think that automakers enjoying record profits can say that to pay everyone what they were paying them 10 years ago is a hardship on the company."

The protest comes as the UAW is preparing for contract talks with the Detroit Three this summer. Before that, the union is collecting feedback from members at its local units to take into its bargaining convention in March. In an e-mailed statement today to the Free Press, UAW President Dennis Williams said hearing the concerns of its employees is why the union is engaging its members.

"The great thing about the UAW is that it is a democratic union," Williams said. "Input from our members is always valued and important."

Williams has said the UAW wants a contract that allows the Detroit Three to remain competitive with Asian rivals, and noted that the union won raises for entry-level workers and a more lucrative profit-sharing formula in its 2011 contract. Still, with all three automakers now earning big quarterly profits, Williams said the union wants to recoup some of the sacrifices it has made in recent years.

Hopefully, that means eliminating the tiered salary system and its disparities, Thompson said.

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