Twin steer and tri-drive operations (policy work complete)
- Scoping >
- Analysing issues >
- Analysing options >
This project aims to unlock significant productivity gains from heavy vehicles utilising twin-steer and tri-axle groups in order to meet the demands of Australia's increasing freight task.
Currently, the mass limits under the heavy vehicle national law relating to heavy vehicles using twin-steer and tri-drive axle groups do not allow for the vehicles to be used to their full payload capacity.
In consultation with stakeholders, we are working on two separate but related proposals to increase the current allowable mass of:
- twinsteer axle prime movers towing a semitrailer
- tri-drive prime movers towing a semitrailer.
The NTC recommended allowing twin-steer prime movers towing a semitrailer to operate with a mass limit of 46.5 tonnes at GML and 49.5 tonnes at HML.
The axle mass limit for a twin-steer axle group that is not fitted with a load sharing suspension system will remain at 10 tonnes.
The axle mass limit for a twin-steer axle group with a load sharing suspension system will be 11 tonnes. This increase will be achieved by amending the Heavy Vehicle (Mass, Dimension and Loading) National Regulation 2013 (the regulations) as part of the HVNL maintenance package to be considered by ministers in 2017.
The NTC also recommended that existing regulations governing the allowable mass limits for tri-drive prime movers towing a semi-trailer should be retained.