Australia's largest transport operator could face a 72-hour strike after the Transport Workers Union won the right to vote on industrial action.
About 8500 workers from Toll Group will take part in the vote after the Fair Work Commission approved a ballot on Tuesday.
Workers at more than 400 yards will be balloted by the Australian Electoral Commission on forms of industrial action, including stop-work action of up to 72 hours.
The TWU wants a guarantee that employees of companies contracted by Toll are paid fair wages.
It also wants Toll to guarantee it won't create separate business units with lower pay rates and different safety standards. "Fighting for the rights and conditions of workers at Toll is part of our fight to protect the rights and conditions of every transport worker in the country," said TWU assistant national secretary Michael Kaine.
"Our members are prepared for this next step in this fight."
The AEC has 28 working days to complete the ballot process.
TWU negotiation team member, Rick Millich, said management had left no option.
"It's effectively pushing us for a permission slip to contract out our jobs to unsafe, substandard operations," Mr Millich said.