DETROIT – United Auto Workers has unexpectedly expanded its U.S. strikes at Ford Motor to a highly profitable SUV and truck plant for the automaker in Kentucky.

The strike was effective at 6:30 p.m. ET Wednesday at Ford’s Kentucky Truck Plant, where the automaker produces Ford Super Duty pickups as well as the Ford Expedition and the Lincoln Navigator SUVs. The facility employs 8,700 UAW members.

The union’s decision to strike the plant, which is Ford’s largest in terms of employment and revenue, is a major escalation in UAW’s targeted, or “stand up,” strikes. It also marks a change in strategy, which has previously included UAW President Shawn Fain publicly announcing the strike targets before the work stoppages occur.

A Ford source said the union informed the company early Wednesday afternoon that it wanted a new economic counteroffer by 5 p.m. ET, followed by a meeting request for 5:30 p.m. ET. that included UAW’s entire Ford bargaining committee, including UAW President Shawn Fain, Vice President Chuck Browning and other top officials.

The source, who agreed to speak on the condition of anonymity because the talks were private, said the meeting lasted less than 10 minutes before Fain said the company “lost Kentucky Truck.”

“The strike was called after Ford refused to make further movement in bargaining,” UAW said in a release. “The surprise move marks a new phase in the UAW’s Stand Up Strike.”

Ford said the “decision by the UAW to call a strike at Ford’s Kentucky Truck Plant is grossly irresponsible but unsurprising given the union leadership’s stated strategy of keeping the Detroit 3 wounded for months through ‘reputational damage’ and ‘industrial chaos.’ ” 

The latter part of the statement refers to leaked private messages last month from UAW communications director Jonah Furman discussing the union’s public posturing of issues and targeted strikes as causing “recurring reputations damage and operational chaos” to the automakers.

The automakers have argued the messages as well as the union’s actions show UAW negotiators were never actually interested in reaching a deal with the Detroit automakers.

“We have been crystal clear, and we have waited long enough, but Ford has not gotten the message,” Fain said in a statement Wednesday. “It’s time for a fair contract at Ford and the rest of the Big Three. If they can’t understand that after four weeks, the 8,700 workers shutting down this extremely profitable plant will help them understand it.”

Ford said the new strike puts at risk approximately a dozen additional Ford operations and “many more supplier operations that together employ well over 100,000 people.”

Ford said it had presented an “outstanding offer” and “has been bargaining in good faith this week on joint venture battery plants,” which have been a recent focus of the talks.

General Motors last week agreed to include workers at its EV battery plant in the company’s national contract with the union, which Fain called a “transformative win.”

Fain said the union expects Stellantis and Ford Motor to follow suit, including battery plant workers in eventual contract agreements.

The UAW has been gradually increasing the strikes since the work stoppages began after the sides failed to reach tentative agreements by Sept 14. The targeted, or “stand-up,” strikes are taking place instead of national walkouts.

The additional workers brings UAW’s total to about 34,000 U.S. workers, or roughly 23% of UAW members covered by the expired contracts with the Detroit automakers, who are currently on strike.