The contracts were approved by a two-to-one ratio and will run until July 27, 2013, the union said.
The agreement covers plants in Akron, Ohio; Des Moines, Iowa; Russellville, Ark.; Bloomington, Ill., and LaVergne, Tenn. A separate agreement was ratified at a plant in Morrison, Tenn.
The United Steelworkers said the new contract protects wages and benefits for current workers and improves health care coverage for new hires.
The USW represents about 1.2 million active and retired members in North America in a wide variety of industries, ranging from paper, steel, tire and rubber and other manufacturing environments to the public sector, service and health care industries.