National Transport Commission (Model Amendments Regulations 2008 (Twin Steer Mass and Loading Limits) Regulations 2009 enable certain heavy vehicles fitted with a twin steer axle group to operate at increased mass.

Once these regulations are reviewed by each state and included into their state regulations, they will have effect.

The Regulations are available at:
http://www.comlaw.gov.au/comlaw/Legislation/LegislativeInstrument1.nsf/0/
CD6A6195177B24E4CA257661007CB504/$file/0910267A090521Z.pdf

The Explanatory Statement is available at:
http://www.comlaw.gov.au/ComLaw/Legislation/LegislativeInstrument1.nsf/0/
DFB80367ADDA4AFECA257661007CB404/$file/F2009L04051.pdf