Updated with results of the voting.

The United Auto Workers union said its members ratified a new four-year agreement with Fiat Chrysler Automobiles (FCAU) - Get Report  on Thursday. It was the UAW's first new labor deal with a Detroit-based automaker since negotiations began in July.

Workers at FCA voted 77% in favor the agreement, the UAW said in a post on the UAW Chrysler Facebook page, as reported by the Detroit Free Press.

Now that the agreement has been ratified, the union will begin negotiations with Ford (F) - Get Report  or General Motors (GM) - Get Report

Newer workers were dissatisfied with the first proposal, insisting on further narrowing of the gap between their wages and those of veteran workers. In 2007, the UAW agreed to a lower tier of wages for new hires in order to relieve financial pressure on the Detroit-based automakers. The latest proposal omits the idea of a health care trust to lower medical costs. 

"I think the second version of the tentative agreement addressed many of the workers' concerns and that's evident in their strong ratification," Kristin Dziczek, director of the industry and labor group at the Center for Automotive Research, told the Detroit News. "There was a clearer path to top-tier wages for the current second-tier workers." 

The conclusion of a contract without a strike and with little rancor would be a victory of sorts for both parties. The UAW is eager to convey an image as a reasonable partner with automotive management, which might help it achieve the goal of organizing non-union plants in the southern U.S. FCA wanted to avoid a costly work stoppage at a moment when demand for vehicles in the U.S. is strong. 

According to terms of the second agreement, younger workers hired after 2007 would be boosted gradually to about $29 an hour or more over the next eight years, like veteran workers. That rate is a boost from a $25.35 ceiling under the rejected contract and $10 an hour more than the current ceiling. 

How the new labor rate will affect FCA's total labor costs wasn't immediately clear, since the contract may contain other provisions that save the automaker money, such as expanded flexibility to employ contract labor, which FCA has been seeking. 

A recent study by the Center for Automotive Research in Ann Arbor, Mich., showed that labor costs for Detroit-based union automakers had dropped dramatically in the past decade, while automotive profits have risen.

Yet the labor cost to foreign-based automakers is still half that of the Detroit-based automakers on a per-vehicle basis. Consequently, the UAW faces a difficult task in achieving its stated goal of organizing so-called "transplant" auto factories in the southern U.S.

The CAR study showed that last year the foreign automakers building cars in the U.S. paid $1,042 per vehicle in labor costs, compared with an average of $2,215 per vehicle for Fiat Chrysler, Ford and GM. But the Detroit Three's hourly average has nearly been halved since the financial crisis of 2008 to 2009 that resulted in bankruptcy for GM and Chrysler, which Fiat acquired.

Doron Levin is the host of "In the Driver Seat" broadcast on SiriusXM Insight 121, Saturday at noon, encore 9 a.m. on Sunday.

The writer has no financial interest in the aforementioned companies.