DETROIT — General Motors and the UAW reached a proposed tentative agreement on a new contract Wednesday, the 31st day of a nationwide strike. 

The autoworkers walked off the job at 12:01 a.m. Sept. 16, launching the union’s first nationwide strike in 12 years. Their four-year contract had expired at midnight Sept. 14.

Autoworkers were bitter about GM announcing plans in November 2018 to idle four U.S. plants and argued it was time for them to be rewarded after making concessions a decade ago to help the automaker rebound from bankruptcy.

During negotiations, it became evident that workers were adamant that temporary workers should get a better deal from GM. The union during the recession a decade ago agreed to expanded hiring of temps by GM, Ford and what then was Chrysler. Those workers are paid $15-$19 an hour with no profit sharing, little time off and no job protection.

The final days of negotiations focused on what the automaker would commit to build at U.S. plants over the four-year life of the new contract. The union pressed for internal combustion vehicle commitments even as GM says it is moving toward an electric future and continues low-cost Mexican production of SUVs and pickups for U.S. sale.

Key issues included:

— Temporary workers. GM wanted the ability to hire more temps to save costs and be able to quickly reduce the workforce in case of a market downturn. The UAW wanted to equalize pay for temps, profit sharing and a path to permanent employment. Similarly, it wanted to even out pay for workers hired after 2007, who start at $17 an hour and can reach $28 after eight years.

— Job security. That’s code for commitments by automakers to invest in U.S. factories and commit to building vehicles here. Detroit automakers in contracts say, given solid market conditions, they will invest in UAW-represented sites and tie that spending to numbers of jobs created or retained.

— Health care. GM is self-insured and spends $900 million a year on hourly workers’ care. UAW members pay just 3% of their costs, compared with 28% for the average U.S. worker. Autoworkers, who argue that their jobs are physically taxing and can lead to chronic injury early in life, won here, with GM agreeing to leave workers’ costs unchanged.

— Pay. Autoworkers’ pay has eroded 16% against inflation since 2010, according to the Center for Automotive Research in Ann Arbor.

The deal was struck only after an acrimonious strike that included bickering over whether the company or union would pay strikers’ health care costs and GM obtaining a court order barring picketers from blocking entry at the company’s Spring Hill, Tennessee, assembly plant. Ten strikers were arrested there in two incidents.

Strikers in several locations in the early days of the stoppage temporarily held up nonunion workers, including salaried GM staff and employees with contractors, assigned to work in the strike-idled plants. While Teamsters honored the UAW picket lines and said they wouldn’t deliver completed vehicles to dealerships, non-Teamster truckers did the work in places, drawing strikers’ ire.

A heated beginning

After the union said its roughly 46,000 GM workers would strike at 55 U.S. locations, GM took the unusual step of making public an overview of what it said was its initial offer to the union.

“We presented a strong offer that improves wages, benefits and grows U.S. jobs in substantive ways and it is disappointing that the UAW leadership has chosen to strike at midnight tonight,” the company said not long after the union said it would strike. “We have negotiated in good faith and with a sense of urgency.”

GM said that prestrike offer included more than $7 billion in U.S. investments over the four-year life of a new deal, more than 5,400 jobs, higher pay and what the company said would be improved benefits.

The union countered the next day that GM might have avoided a strike had it not “waited until just two hours before the contract expired to make what we regard as its first serious offer.”

Teamsters said they would honor UAW picket lines and not deliver vehicles finished before the strike to dealerships, but GM used non-Teamster truckers to move vehicles out of plants, at times prompting confrontations with picketers.

That was Day One.

The next day, GM ended health care for the strikers, kicking that cost to the union’s strike fund, which held nearly $800 million for costs such as health care and strike pay of $250 a week. While the union had anticipated taking over health care costs, it said it was blindsided by GM’s announcement.

GM backed off on the move 12 days into the strike, saying it would continue to cover health care.

Collateral damage

Many suppliers began temporary layoffs a few days into the strike, and GM plants in Canada and one in Ohio that is represented by an electrician’s union rather than the UAW shut down because they were short on parts.

On Oct. 1, GM’s Silao Assembly in Mexico, which builds the highly profitable Chevrolet Silverado and GMC Sierra pickups, was forced to shut down because of a parts shortage, bringing to at least 10,000 the number of workers laid off in North America because of the strike.

The Center for Automotive Research estimated:

— GM was losing $450 million per week.

— More than 575,000 workers nationwide are in industries directly or indirectly affected by the UAW strike, including supplier firms to GM and firms in the broader economy where striking and laid-off workers shop.

— Lost wages each week of some $857 million.

— Lost tax revenue includes $114 million in personal income tax and $108 million in lost revenue that supports social insurance programs such as Medicare and unemployment insurance.

Despite the tension, negotiators worked into the evening each day of the strike.

On Oct. 9, GM CEO Mary Barra, concerned about the lack of progress, met with UAW President Gary Jones and the union’s GM Department vice president, Terry Dittes, for an hour.

Sources at the time said that meeting reinvigorated talks that had slowed, but Thursday and Friday were among the most acrimonious days of the monthlong strike. The union said GM was “playing games” and not taking it seriously. GM said the union was dragging its heels and outlined its latest offer in a letter to all its employees, including the strikers.

Janitor strike

The autoworker strike is one of two UAW strikes against GM facilities. Maintenance workers with Aramark, with which GM contracts for services, struck five sites in Michigan and Ohio 24 hours before the autoworkers went on strike.

The 850 striking Aramark janitors are paid from $11-$15.18 per hour and had been working on a contract extension since March 2018. They described some of the work they do as dangerous, using extremely high-pressure water to clean equipment in the paint shop, for example.

People close to GM and the UAW told the Free Press it was important to reach a tentative new contract with Aramark around the same time as reaching one with GM. Otherwise, UAW workers for either side face the possibility of crossing the others’ picket lines.

What happens next

The tentative agreement will be reviewed by the National GM Council, which has been summoned to a meeting Thursday morning in Detroit. If the council approves it, the proposed pact will be submitted to UAW-represented GM employees for ratification.

The negotiations have been conducted under a cloud cast by a corruption investigation that has led to nine convictions of union and auto officials. Days before the contract expired, regional director Vance Pearson was charged with lavish spending of union money for himself, and court documents in the case implicated union president Jones, whose house. Pearson was suspended from his position three weeks into the strike.

The ratification vote will be a measure of members’ trust of their leaders to negotiate a good deal that they must live with for the next four years.

The union chose to negotiation first with GM to create a template that it will soon take to Ford and Fiat Chrysler Automobiles, whose UAW contracts were extended while the union negotiated with GM.

All told, the UAW represents 148,000 workers for the three Detroit automakers.