Jim McNamara, a spokesman for the union, said an agreement had been reached with the Metropolitan Marine Maintenance Contractors Association (Metro), avoiding any demonstration or strike.
The union said the dispute had to do with language that had been inserted into the contract during negotiations requiring all containers and chassis to be inspected at terminal depots to ensure equipment is safe and roadworthy before being released.
Terminal operators were concerned about their power to insist on inspection or repair of equipment not owned or operated by steamship lines and their chassis pools, for example chassis owned by trucking companies.