Firefighters have major concerns for the state of fire trucks, with nearly half of their newest vehicles pulled off the road.
They're relying on older vehicles to carry out their work.
In a separate case, they are relying on a rental van due to a vehicle being out of action.
It has no sirens and it can't drive over the speed limit, but it's expected to respond swiftly to major fire emergencies.
"It's incredibly frustrating, it's just beyond belief as to how we can be in this situation," the Firefighters' Union's Martin Campbell told 1 NEWS.
It's just one of many issues firefighters say they're dealing with as faults in their newest trucks have forced half of country's fleet off the road.
Small cracks in the supports that hold up the lockers on the side of the trucks are causing the issue.
"The problem with the contingency plan is there isn't one," Mr Campbell said.
"If there's a major emergency, we have no relief fleet that can be used to respond to that because all of the relief trucks are currently being used to replace the broken-down Man trucks that were in commission."
Fire and Emergency New Zealand's Russell Wood says the rental van isn't being used as a front-line appliance.
It is covering a salvage tender that is being serviced.
"It goes in after an incident is in wind-down mood and helps with the clean-up in the salvage process," he told 1 NEWS.
He said they were working with their supplier to identify the root cause of the issue with the Fraser-Man trucks.
"Until we can do that definitively and get that pair reviewed by a vehicle engineer, we don't know ultimately what the solution will be."
It's not the first time these Fraser-Man-type trucks have had problems. In 2016, firefighters blacklisted some of their appliances after more than 200 faults were reported.
"I think we could always do better at that and I think that's worth putting quite a comprehensive process in the current project to look at the future, the next generation appliance," Mr Wood said.
Of the 41 trucks inspected, 23 showed evidence of cracking and have been taken out of operation service, Mr Wood says.