The union for Boeing's engineers and technical workers is counting ballots Tuesday on a contract offer and whether to authorize a strike.
The union, Society of Professional Engineering Employees in Aerospace, is recommending that members reject the offer because it would not provide pensions to new employees. They would have a 401k retirement plan instead. The union calls that unacceptable.
Chicago-based Boeing says the change is important to the company's future.
The union also wants the authority to call a strike if subsequent negotiations fail.
The union represents 23,000 employees, mostly in the Puget Sound region. Negotiations began in April and union members rejected one offer in October. The previous contract expired in November.
SPEEA went on strike for 40 days in 2000.