Mayor chuck reed cited 1,800 other city employees who took cuts and a $10 million budget deficit.
"It's reality, it's the hard facts. We don't have the money to keep firefighters because the cost of them is out of control," he said.
The city asked the union for this vote two weeks ago and members resent that.
"I think he is trying to control every employee group, and the firefighters here are the last, and are going to stand up," firefighter Robert Sapien said.
The union went on the offensive by using two simultaneous Thursday morning fires as bargaining chips. It says reduced service increased the response time, and left other parts of San Jose vulnerable.
"If one more fire or medical emergency would have occurred, we would not have been able to respond," San Jose Firefighters Union President Randy Sekany said.
The union hopes for help from the city council.
"We see holes and need to think about where to spend public money for the protection of our community," San Jose City Councilwoman Nora Campos said.
"In a perfect world, we would have more firefighters. In a perfect world, they would have taken the 10 percent cut and heeded my job to save jobs and services," San Jose Mayor Chuck Reed said.
"I say that we will continue to try to get them back. I say they should look for an employer who appreciates them. Clearly, the city does not," Sekany said.
If nothing changes, the stand-off between firefighters and the city goes to binding arbitration next November. One sticking point for the union is that even it took the pay cuts, the city cannot guarantee those 49 jobs in the next contract.