Heavy vehicle rollaways remain one of the most preventable risks across New Zealand’s transport, utilities and civil construction sectors.
In many cases, these incidents stem from human error in applying a park brake. And, in vehicles fitted with cardan shaft braking (CSB) systems, that risk is amplified.
Recent coronial findings and safety alerts have brought renewed focus to this issue, with calls for more to be done to address the safety risks impacting 35% of heavy vehicles on New Zealand’s roads so that no further deaths occur.
Between 2018 and 2025, approximately 80% of contributing factors in heavy vehicle crashes in New Zealand were attributed to human-related factors, according to NZ Transport Agency data. (1)
New Zealand’s road safety strategy, Road to Zero (2020–2030), recognises this reality. It accepts that people will make mistakes, and that those mistakes should not result in death or serious injury.
This shifts the focus beyond the driver. It places responsibility on strengthening all parts of the transport system, including vehicle design, safety technology and operating protocols, so that when mistakes occur, they are less likely to result in harm.
For operators of heavy vehicles, particularly those working in high-risk environments, this has clear implications.
Cardan shaft park brake systems are commonly found in smaller to medium trucks and some passenger service vehicles operating in New Zealand.
Unlike conventional braking systems, a cardan shaft brake does not apply force at the wheels. Instead, it applies a clamping force to the driveshaft at the rear of the gearbox.
While effective within design limits, the system has known operational constraints.
Drivers must apply sufficient force to the handbrake – often described as requiring a full “eight clicks” – to achieve adequate clamping force. For those unfamiliar with the system, or moving between vehicle types, it can be difficult to judge whether the brake has been fully engaged. Dashboard indicators do not always provide clear confirmation.
Even when correctly applied, other factors can affect performance. These include load weight, incline, traction conditions and mechanical adjustment of the brake tension. A vehicle that appears secure may not remain so.
In New Zealand, vehicles fitted with cardan shaft brakes are subject to regular Certificate of Fitness (CoF) inspections, typically every six months, where braking systems are tested to defined standards. While this is an important safety control, it does not remove the operational limitations of the system in day-to-day use.
In late 2025, following an inquest into a fatal 2018 incident, Coroner Erin Woolley described reliance on cardan shaft brakes as a sole park mechanism as “inherently dangerous”, noting that such systems can fail without warning.
Most heavy vehicle rollaways occur when the driver is not in the vehicle.
Drivers working in civil construction, utilities, waste management and delivery operations frequently enter and exit their vehicles throughout the day. Tasks may include loading, unloading, vehicle inspections or interactions with other workers.
In these environments:
In the case of cardan shaft systems, these small variations can have serious consequences.
Addressing this issue requires more than procedures and training alone.
It requires an engineering control that reduces reliance on perfect human behaviour.
The MAX-SAFE Anti-Rollaway Brake System™ has been developed to address this specific risk.
The system continuously monitors key vehicle inputs, including park brake position, driver seat status and door position.
If a driver attempts to exit the vehicle without the park brake being fully applied, the system provides immediate audible and visual warnings while the driver is still in a position to correct the issue.
By doing so, the system addresses the most common cause of rollaway incidents – incomplete or incorrect application of the park brake.
Importantly, the solution does not replace or modify the underlying braking system. It works within the vehicle’s operating parameters and provides an additional layer of safety.
Since 2022, the MAX-SAFE Anti-Rollaway Brake System has been installed on more than 500 heavy vehicles across New Zealand through Autokraft Electrical and Diesel (AED), SGESCO-MAX’s authorised distributor.
Adoption is occurring across multiple sectors, including civil construction, utilities, waste management, and delivery and logistics.
These are environments where vehicles operate on varied terrain and where drivers regularly enter and exit vehicles as part of normal operations. In these conditions, reducing reliance on perfect brake application is a practical step toward improving safety outcomes.
“We are addressing the most common cause of rollaways, which is human error in applying the park brake,” said Scott McPherson, Managing Director of SGESCO-MAX. “If we can remove that, we significantly reduce the risk.”
This approach aligns with New Zealand’s broader road safety principles – recognising that people will make mistakes and putting measures in place to provide better preventative safety when those mistakes occur (2)
There are an estimated 70,000 vehicles in New Zealand fitted with cardan shaft park brakes. This represents approximately 35% of the heavy vehicle fleet. (3)
While some operators are moving toward alternative braking systems, a significant number of these vehicles remain in service. Additionally, around 1,500 vehicles fitted with this technology continue to enter the New Zealand fleet each year. (4)
Given the known limitations of cardan shaft systems, and the findings from coronial investigations, there is increasing recognition that relying on procedure alone is not sufficient.
Engineering controls that reduce human error are becoming an important part of managing this risk.
For companies that espouse safety as a core value, where a known risk exists and a practical solution is available, taking action is responsible, necessary and ethical. Where it is not, the decision becomes harder to justify.
The MAX-SAFE Maximum Safety Anti-Rollaway Brake™ solution
(1) https://nzta.govt.nz/assets/About-us/docs/oia-2025/oia-18497-attachment.pdf
(2) https://www.transport.govt.nz/assets/Uploads/Consultation/Road-to-Zero-summary-document.pdf
(3) https://www.nzta.govt.nz/assets/About-us/docs/oia2-2023/cardan-shaft-brake-review-2023.pdf
(4) https://transporttalk.co.nz/news/industry-seeks-feedback-on-cardan-shaft-park-brakes#