A major truck distributor is investigating three trailer tow bars that failed to see if it needs to order a recall of about 600 vehicles.
File image. Photo: 123RF
So far the research pointed to not intervening, it said.
The tow bars on three small Mistubishi Fuso trucks were damaged backing into metal piles.
However, their design then came into question so they were sent off and subjected to 1.5 million cycles of testing.
Fuso New Zealand managing director Kurtis Andrews said tow bar supplier Best Bars had told them they did not need to fit stronger bolts.
"We are investigating a very, very small select few tow bars that have failed, but they have failed at this point subject to abuse.
"The testing report that we've had back from Australia shows that the current design is OK to continue with."
Best Bars had gone back to the drawing board and said, "let's retest it", Andrews said.
Fuso had asked dealers for feedback too.
"There are no issues with road safety," he said.
"The tow bars are safe so we're pretty happy to continue as we are," though he noted they were yet to make a final decision on a recall.
Best Bars had advised it to keep things as they were, and any move to upgrade the bolts would come at "quite a significant cost", he said.
"We are pretty serious about the way we do business and if there was a major ongoing failure, we would absolutely put in a recall and put it through NZTA."
One option would be to add extra bolts when trucks came in for servicing, he said.
The New Zealand Transport Agency - Waka Kotahi - said it was not involved as any recall would be voluntary.
"If requested we'll provide the manufacturer administering the recall with contact details of vehicle owners as per our standard processes," Waka Kotahi said.
RNZ has approached Best Bars for comment.
It is understood Waka Kotahi advised that if it did come to putting bigger bolts on the trailers, that would not need certification from a heavy vehicle engineer. RNZ has asked the agency about this.