DETROIT — General Motors said it was extending downtime at several crossover assembly plants in North America as the global shortage of microchips drags on, but production at plants that make its lucrative pickup trucks and SUVs full size will continue.

“These most recent scheduling adjustments are driven by ongoing parts shortages caused by semiconductor supply constraints in international markets under COVID-related restrictions,” the automaker said in a statement Thursday. “While the situation remains complex and very fluid, GM continues to prioritize full-size truck production which remains in high demand.”

Seven of GM’s plants in North America will open next week: its full-size pickup plants in Flint, Michigan, Fort Wayne, Ind., and Silao, Mexico; its full-size SUV plant in Arlington, Texas; its Chevrolet Corvette plant in Bowling Green, Ky.; its GMC Acadia, Cadillac XT5 and XT6 plant in Spring Hill, Tennessee; and Fairfax Assembly in Kansas, which will only build the Cadillac XT4.

AutoForecast Solutions estimates that automakers will eliminate 9.4 million vehicles from their production schedules worldwide due to chip shortages. So far, they’ve lost 8.2 million vehicles, including 2.6 million in North America.

Last week, GM Chief Financial Officer Paul Jacobson said the automaker stood to lose about 200,000 vehicles in the second half due to chip shortages, doubling an August projection.

But GM is sticking to its full-year financial guidance and expects broader chip distribution in 2022.