The strike will include two locations in Pennsylvania, three in Maryland and one in Florida.
"UAW members get up every day and put in long, hard hours of work from designing to building Mack trucks," Ray Curry, Secretary-Treasurer of the UAW and Director of the Heavy Truck Department, said in a statement. "UAW members carry on their shoulders the profits of Mack and they are simply asking for dignity, fair pay and job protections."
The UAW's list of "unresolved issues" is long. It includes wage increases, job security, cost-of-living adjustments, wage progression, skilled trades, shift premium, holiday schedules, work schedules, health and safety, seniority, pension, 401(k), healthcare and prescription drug coverage, overtime, subcontracting and temporary workers.
"We are surprised and disappointed that the UAW decided to strike, rather than to allow our employees to keep building trucks and engines while the parties continued to negotiate. The positive working relationship between local UAW leadership and management at our facilities was clearly in evidence throughout the negotiations, and progress was being made," Mack Trucks President Martin Weissburg said in a statement.
He added that the company is part of the only heavy-truck manufacturing group that assembles all of its trucks and engines for the North American market in the U.S.
"The last four years we have helped Mack Truck make significant profit through our work," Doug Irvine, president of Local 2301 in Baltimore and President of the Mack Truck Council. "All we are asking is that the company treat us with the dignity and respect we deserve in making them successful."
The decision comes as the UAW's nationwide strike against General Motors is a few days away from its one-month mark. That strike affects nearly 50,000 workers.
The local unions going on strike are in Allentown, Pennsylvania; Middletown, Pennsylvania; Hagerstown, Maryland; Baltimore and Jacksonville, Florida.