A 2008 study found that New Zealand road freight costs are 30% higher on average than in Australia. One of the major causes was that Australian trucks could carry a lot more, with a 62.5 tonne maximum weight compared to 44 tonnes here, and longer at 25 metres while the New Zealand maximum length was 20 metres.
In 2009 the Government was persuaded by the Road Transport Forum to trial 50-tonne trucks. The results of the trial and other research showed productivity could increase by 10 to 20 percent, trip numbers could reduce by 16 percent, fuel use by 20 percent with an overall increase in GDP in the range of $250 - $500 million per annum.