The United Auto Workers union announced this morning that it had reached a tentative agreement with General Motors that could end the month-long strike by 48,000 GM workers, the longest national auto strike since 1970.

The UAW’s national GM Council, a 175-member body of local union officials, will meet tomorrow morning in Detroit to back the deal and send it to the membership for ratification.

GM workers and all autoworkers must be warned: This agreement can be nothing other than a historic betrayal that will, if imposed on the rank-and-file, open the way for a major expansion of temporary labor and the transformation of the workforce into low-paid contingent laborers at the disposal of the auto bosses and their Wall Street creditors.

The sure sign of a sellout is the continued silence from the union on the content of the negotiations and the deal that has been reached.

Workers must organize now to oppose and defeat any contract that fails to abolish the tier system, transform all temps into full-time workers with full pay and benefits, raise pay and benefits to recoup the losses from four decades of concessions, and reject company demands for higher out-of-pocket health care costs.

There must be no return to work without a ratification vote, and workers must be given a week to study the full contract proposal, including all side agreements, before voting on the deal.

Rank-and-file monitors must be present to oversee the voting to prevent ballot-stuffing or other forms of vote-rigging.

The first step is to establish rank-and-file committees independent of the union in all plants to take the conduct of the strike out of the hands of the bribed company stooges who run the UAW.

There is little doubt that the GM Council will rubber stamp the deal, but the question remains whether the UAW feels workers have been sufficiently worn down and economically impacted to send them back to work before they have had a chance to vote on it. Either way, the local union presidents, shop chairs and other officers at tomorrow’s meeting will be given their marching orders to push through the deal with the kind of lying and bullying tactics that were employed to override rank-and-file opposition in 2015 and in previous contracts.

The UAW claims it has “achieved major wins for UAW-GM members,” just as it has claimed in every contract betrayal of the past 40 years. UAW Vice President Terry Dittes issued a statement saying: “[W]e will refrain from commenting on the details until the UAW GM leaders gather together and receive all details.” Demonstrating his contempt for the intelligence of the workers, he added that the union tops were concealing the content of the deal “out of respect for our members.”

A major factor in the UAW’s rush to shut down the walkout is the growing strike wave across the country, which threatens to break the union’s isolation of the GM workers.

Earlier this week, thousands of UAW Mack-Volvo truck workers walked out at plants in three states. They were joined by thousands of copper miners in Arizona and Texas. Tomorrow nearly 30,000 teachers and support staff are set to strike in Chicago, the third largest city in the US.

From the beginning, the “negotiations” between the UAW and GM have been a farce, given that both parties had already agreed to continue the decades-long reduction in labor costs. Over the last 14 years alone, the UAW has enabled GM to reduce its hourly labor costs by a staggering two-thirds, from $16 billion in 2005 to $5 billion today.

According to sources cited by Reuters and other media outlets, the deal drafted over the last few days includes a signing bonus of $9,000 for full-time workers and $3,000 for temps. GM has also proposed 3 percent pay raises in the second and fourth years of the four-year-contract and 3 percent and 4 percent lump sum payments in the first and third years respectively.

While none of the leaks to the corporate media can be taken at face value, the New York Post reported Tuesday that the UAW and GM had “agreed in principle” to give temporary workers “the opportunity to become full-time workers after three years of consecutive service.” This is a meaningless provision since there would be nothing to stop the company from repeatedly laying off temporary workers before they reach the three-year threshold. Its real purpose would be to provide a cover for a major expansion of temporary labor both in absolute terms and as a percentage of the UAW workforce.

While GM’s stock went up 2.5 percent on the news of a deal, the Wall Street Journal expressed fears that it would meet with widespread resistance from striking workers. It wrote: “There is no guarantee workers will approve the tentative agreement. If they vote the first proposal down—as did Fiat Chrysler workers in 2015—company and union negotiators will have to return to the bargaining table to hash out a deal they believe the members will support.

“A potential wild card for union leaders is roughly 42 percent of GM’s factory workers have never seen an industry downturn and might be a harder sell on any deal that doesn’t fully meet all their demands, according to people close to the negotiations.”

Among rank-and-file workers there is enormous opposition to another sellout. “This contract is going to show which side the UAW is on,” Joe, a young worker at GM’s Detroit-Hamtramck Assembly Plant, told the WSWS Autoworker Newsletter. “They’ve supposedly been negotiating night and day, but if this is not the right contract, I’m going to vote ‘no.’ We’ve lost too much money in every contract.”

Further discrediting the UAW is the exposure that its top officers took millions in bribes and kickbacks, pilfering union dues and company money funneled through the joint training centers such as the UAW-GM Center for Human Resources. The corruption scandal has already led to the conviction of former UAW bargainers who negotiated contracts that saved the companies billions and has implicated UAW President Gary Jones.

Wall Street has made it clear it will torpedo GM stock prices if executives retreat in the slightest from the bankers’ demands that the company cut another $500 million in annual labor costs—roughly $5 an hour—and create a “flexible manufacturing force” of largely at-will employees as GM transitions to electric and autonomous vehicles.

In a note to investors Tuesday, Bank of America analyst John Murphy said, “A prolonged strike could burn significant cash and bring GM to its knees, but investors likely will also react negatively if management is perceived to have caved into labor’s demands and GM’s long-term competitiveness is threatened.”

GM workers must act now and form rank-and-file committees to take the conduct of the strike out of the hands of the corrupt UAW and expand the strike to Ford, Fiat Chrysler and the parts industry. Autoworkers must unite with striking Mack-Volvo truck workers, Arizona and Texas copper miners and Chicago teachers to begin the mobilization of the entire working class against the decades-long assault on jobs and living standards.