Four years ago, the creation of an eight-year "grow-in" period for new hires to earn top wages was celebrated as a victory in the UAW's quest to eliminate the two-tier wage system that many workers despised.
Now, General Motors' resistance to letting workers attain full pay faster is seen as one of the reasons the union has been on strike since mid-September. UAW members today argue that eight years is too long to wait, especially as the automakers amass record profits and dole out lucrative bonuses to executives.
Labor experts say there's recent precedent for quicker paths to earning top dollar, making it an issue on which the two sides could find compromise.
"The UAW is determined to make headway, in part because the notion of equal work for equal pay goes to the very heart of the union," Harley Shaiken, a University of California at Berkeley professor who studies labor issues, told Automotive News. "Their motto is solidarity forever, and this gnaws at that. Some major movement here is going to be necessary to get a deal ratified."
On Tuesday, the UAW said it rejected GM's latest offer and made a counteroffer.
"This proposal that the Company provided to us on day 15 of the strike did not satisfy your contract demands or needs," Terry Dittes, director of the UAW's GM department, said in a letter to members. "There are still many important issues that remain unresolved."
The offer "came up short" in many key areas, such as health care, wages, temporary employees, skilled trades and job security, Dittes said.
UAW leaders have been trying to undo the two-tier wage structure since shortly after the membership agreed to it in 2007 as a means of helping the Detroit 3 save money and stay in business during the Great Recession. It divided plants' work forces into legacy workers making around $28 an hour and new hires making as little as $14 an hour.
It's a practice that has become increasingly common among unions. The Teamsters, which represents UPS drivers, last year implemented a two-tier system, despite protests, that caps certain "hybrid" drivers below the $40 made by standard drivers.
During the last round of bargaining in 2015, UAW workers at Fiat Chrysler Automobiles rejected a tentative agreement that called for the so-called "second tier" workers to get raises but still top out at a little over $25 an hour, not quite as much as those hired prior to 2007. The two sides went back to the negotiating table and came up with the eight-year path to equal wages, which was approved at all three companies.
"It was a start," said Tim Duplanty, a member of UAW Local 598 at Flint Assembly. "That was what we could get at the time, but we're in a different time now."