UPDATE 6-Auto workers brace for more strikes as UAW, Big Three remain at odds

(Adds comments from workers in Detroit in paragraphs 7 and 10, recasts first two paragraphs, changes headline)

By Ben Klayman, David Shepardson

TOLEDO, Ohio, Sept 19 (Reuters) -

United Auto Workers members picketing in Michigan and Ohio urged union leaders to hold firm on their biggest demands on pay hikes and compensation as their first-ever strike against the Detroit Three automakers hit its fifth day.

The UAW says it will strike against more U.S. plants on Friday if no serious progress was made in talks with automakers. The UAW launched a strike against Ford, General Motors and Chrysler parent Stellantis, last week, targeting one U.S. assembly plant at each company. Workers on the picket lines in Wayne, Michigan, and Toledo, Ohio, on Tuesday said the union should not back down on its demands, with some hoping Friday's deadline for more strikes would produce results.

Still, it was not clear when official negotiations between the two sides would resume after lengthy talks on Monday brought little progress, prompting concerns among some auto executives and congressional aides that a deal will not be struck before the Friday noon deadline.

"I’m going to vote no on the contract until they get it right. I know we won’t get everything, but we gave up a lot in 2008 with the recession," said Laura Zielinski, 55, who has worked at the Stellantis Jeep plant in Toledo for more than 28 years. "I’ll do it as long as it takes."

The U.S. strike is now in its fifth day, with some 12,700 of the UAW's 150,000 total members who work at the Big Three on strike. Analysts expect plants that build more profitable pickup trucks like Ford's F-150, GM's Chevy Silverado and Stellantis' Ram would be the next targets if the walkout continues.

"Hopefully they get things resolved within this week,” said Candis Holmes, 35, who works at Ford's Wayne, Michigan, assembly plant, one of three affected by the strike.

The union and companies are at loggerheads over pay and benefits for workers. The three automakers have proposed 20% raises over the 4-1/2-year term of their proposed deals, though that is only half of what the UAW is demanding through 2027.

Workers have also pushed automakers to eliminate a tiered pay structure that pays newer workers much less for the same jobs than veterans and sought improved cost-of-living adjustments to wages.

"We want them to end tiers because everybody deserves to make a livable wage," said Holmes, who has worked at Ford for eight years.

The strikes have halted production at plants in Michigan, Ohio and Missouri that produce the Ford Bronco, Jeep Wrangler and Chevrolet Colorado, alongside other popular models.

The White House said on Tuesday that acting Labor Secretary Julie Su and adviser Gene Sperling will continue to speak to all sides from Washington instead of traveling to Detroit.

Ford on Friday furloughed 600 workers who are not on strike at the Michigan Bronco plant because of the impact of the work stoppage. GM said it expected to halt operations at its Kansas car plant early this week because of the strike at its nearby Missouri plant, affecting 2,000 workers.

'SUBSTANTIVE OFFER' IN CANADA

Separately, a Canadian union extended its deadline for negotiations at Ford's operations in Canada by one day. Ford's contract with Canadian union Unifor, which represents about 5,600 workers at three plants in Canada, expired at 11:59 p.m. EDT on Monday (0359 GMT on Tuesday).

Unifor said early on Tuesday that negotiations had been extended for 24 hours after it received a "substantive offer" from Ford but that Unifor members should "maintain strike readiness." A walkout by Canadian workers that shuts those engine plants could cripple U.S. production of Ford's most profitable vehicles, even if the UAW decides not to order walkouts at truck plants in Kentucky; Dearborn, Michigan; and Kansas City, Missouri.

Ford said it had agreed to continue negotiations beyond the deadline in hopes of reaching a tentative agreement.

(Reporting by David Shepardson in Washington, Jahnavi Nidumolu in Bengaluru and Ben Klayman in Toledo, Ohio Editing by David Gaffen, Jamie Freed, Matthew Lewis and Deepa Babington)