The road to ratification hit a small speed bump Sunday night as a majority of workers at Ford Motor Co.’s largest plant — Local 249 in Kansas City — voted against a tentative labor deal between the automaker and union.

About 54 percent of production workers voted against the pact, while a slim margin of 50.2 percent of skilled trades workers voted for the deal, according to the union.

Kansas City is critical to Ford’s operations. It builds the profitable F-150 pickup and Transit Van. The union threatened to strike there earlier this year when the two sides couldn’t come to an agreement on a local contract, but they avoided a work stoppage hours before the deadline by agreeing to a deal.

It’s scheduled to receive $200 million in new investments over the four-year pact.

More than a quarter of Ford’s 52,900 workers have had the opportunity to vote on the deal, and despite Kansas City’s results, a majority still favor it.

Earlier Sunday night, a majority at Local 2000, which represents roughly 1,450 workers at Ford’s Ohio Assembly Plant, also voted “yes.” About 51 percent of production workers and 55 percent of skilled trades workers voted in favor of the deal, according to the union.

Under the tentative contract, the Ohio Assembly plant would receive $250 million in new investments, including the addition of a new product. Earlier this year, Ford moved its medium-duty truck production to the plant after years of making the F-650 and F-750 in Mexico.

A majority of workers at Local 897, representing 900 workers at Buffalo Stamping, voted against the deal. About 61 percent of production workers and 54 percent of skilled trades voted against the deal.

So far, four plants — Local 249, 987, Local 228 of Sterling Axle and Local 898 of Rawsonville — have had a majority of workers vote against the deal. On Saturday, Local 588 of Chicago Stamping voted in favor of the deal, and on Friday, three plants, including Michigan Assembly, voted yes. Thursday results came from a couple of smaller plants and results were mixed.

The “no” votes from Sterling Axle and Rawsonville were somewhat expected; workers at those two parts plants — and at Woodhaven Stamping — are set to make a lower wage than their counterparts at other assembly plants.

Second-tier workers can make up to $19.86 an hour, while first-tier workers can make about $22 an hour. The Big Three traditionally have paid parts workers a lower wage because they compete with lower wage, non-union suppliers for the same products.

Voting is scheduled to continue through at least Wednesday. No plants are scheduled to release results Monday

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