DETROIT (AP) — The United Auto Workers union has turned up the heat on General Motors as 5,000 workers walked off their jobs Tuesday at a highly profitable SUV factory in Arlington, Texas.

The move comes just a day after the union went on strike at a Stellantis pickup truck factory in Sterling Heights, Michigan, north of Detroit.

The Texas strike brings the total of UAW members that have walked off their jobs to 46,000 in a series of strikes that is entering its sixth week.

UAW President Shawn Fain last week threatened further strikes in an effort to get GM, Ford and Stellantis to increase their pay offers.

But GM CEO Mary Barra said on Tuesday morning’s earnings conference call that the company already has made a record offer and won’t agree to a contract that jeopardizes the company’s future.

The Arlington factory makes large truck-based SUVs that are among GM’s most profitable vehicles. They include the Chevrolet Tahoe, GMC Yukon and Cadillac Escalade.

The union said the move came just hours after GM announced quarterly earnings and four days after Fain said GM’s latest offer wasn’t large enough.

GM on Tuesday posted a net profit of just over $3 billion for the quarter, down 7% from a year ago. But the company reported strong demand and prices for its vehicles.

Fain said in a prepared statement that GM beat Wall Street expectations, and its offer lags behind Ford, preserving a two-tier wage structure and offering the weakest 401(k) contribution of all three companies at 8%. “It’s time GM workers, and the whole working class, get their fair share,” Fain said.

Barra said GM’s record offer rewards employees but doesn’t put the company or UAW jobs at risk. “Accepting unsustainably high costs would put our future and GM team member jobs at risk, and jeopardizing our future is something I will not do,” she said in a statement.

After the Arlington strike was announced, GM said that it’s disappointed in the escalation, calling the strike “unnecessary and irresponsible.” The strike is harming employees and will have “negative ripple effects on our dealers, suppliers, and the communities that rely on us.”

Automakers have made layoffs since the strike began and blamed walkouts for the job cuts.

Last week GM made an offer that increased its previous offer by about 25% in total value, the company said.