Fiat Chrysler's unionized workers voted overwhelmingly to approve a new four-year deal with the company. This means all three Detroit automakers have been settled by the United Auto Workers union.

After a 40-day strike, General Motors employees accepted a settlement in October, while Ford Employees agreed in November.

The UAW said on Wednesday that 71 percent of Fiat Chrysler employees voted for the contract. At Fiat Chrysler, the group has about 47,000 members.

The labor contract with union workers comes as Fiat Chrysler attempts to finalize a merger deal with PSA Group, the French auto company that manufactures Peugeot cars.

The Deal: $9,000 Signing Bonus

Fiat's deal with UAW includes a signing bonus of $9,000 per employee. The company has also announced new investments worth $4.5 billion in U.S. factories.

A preliminary agreement was reached with Fiat Chrysler on November 30. The new contract also includes a combination of lump sums and salary increases for long-term jobs, full salaries for new hires within four years, and a path to full time for temporary employees after three years of work.

Moreover, the Fiat Chrysler deal adds 12.5 million to the income-sharing equation of the union workers, giving them $900 per 1 percent of the North American profit margin. That's up from $800 and it's lifted a $12,000 limit.

The UAW says the deal creates more than 7,900 jobs, including an additional investment of $4.5 billion previously announced at two Detroit factories.

An agreement to build fresh models from the underpinnings of the Jeep Cherokee SUV and invest $55 million in the Belvidere, Illinois, assembly plant where the Cherokee is being assembled is also included.

Spending Galore

The company will spend $160 million to recruit 100 more people to build a plug-in hybrid version of the Wrangler at the Toledo, Ohio, North Assembly plant that manufactures the Jeep Wrangler SUV. By continuing to build the Jeep Gladiator truck, the Toledo South plant will get $120 million.

Fiat Chrysler will spend $210 million at an assembly plant in Sterling Heights, Michigan, to continue building light-duty Ram pickup and new high-performance truck models.

The truck plant in Warren, Michigan, will receive $2.8 billion for spending on research and construction of the Ram pickup and a new three-row SUV named the Wagoneer and Grand Wagoneer. A hybrid plug-in a version of the SUV will be released in 2021.

The ratification comes as a corruption and embezzlement crisis rocked the International UAW which started at the jointly-run Fiat Chrysler-UAW training center.

Federal officials were alleged to have taken bribes to influence contract negotiations by two former vice presidents who negotiated with FCA.