The union representing aircraft mechanics at UPS. after reaching what they say is an impasse in contract talks with management, has drafted a letter to President Donald Trump seeking his help.

“After listening to you speak about hardworking Americans, we were hopeful that the Tax Cuts and Jobs Act would give us needed financial relief,” Teamsters Local 2727 wrote in the letter that has accumulated hundreds of online signatures on website medium.com.

The letter adds that the aircraft mechanics have gone without a raise for more than four years, and it closes asking Trump if there is "anything you can do to help."

In pushing for the tax cuts, “one of the big things they had promised was that the middle class were going to be getting a wage increase,” said Tim Boyle, president of Teamsters Local 2727. “We’ve got nothing.”

The union, which represents about 1,200 aircraft mechanics and related workers at UPS, plans to give the letter to members of Congress in a meeting Wednesday and ask that it be delivered to the president.

UPS said it “continues to negotiate in good faith,” and added: “We are ready, willing and able to return to the table whenever the [National Mediation Board], which controls the pace and timing of negotiations, deems it advisable.” The company added that aircraft mechanics are paid as much as $105,000 per year. The union says sticking points in talks include rising health care costs.

Separately, the union has filed a lawsuit against the company to stop it from outsourcing maintenance work to third-party contractors overseas. The union alleges the work “is contractually reserved” for U.S.-based mechanics.

The company said its aircraft maintenance practices “meet or exceed FAA regulations.”

“UPS believes we are within our contractual rights with the completion of this maintenance work,” the company said in a written statement. “We believe the action is without merit.”

Meanwhile, the pilots union at UPS has raised concerns that the company is outsourcing flying to other carriers to handle ongoing growth in e-commerce shipments, and commissioned a survey of major shippers on reliability.