High Productivity Motor Vehicles (HPMV) including 50MAX are trucks that are able to operate above the current 44 tonne weight limit under permit.
50MAX vehicle combinations have one more axle than conventional 44-tonne vehicles combinations, meaning the overall truck load is spread further and there is no additional wear on roads per tonne of freight. This means 50MAX gives operators an option to carry increased payloads on parts of the network that, while economically important to New Zealand, carry lower volumes of freight.
The increased payloads of 50MAX can lead to economic benefits for producers, customers and our communities. Allowing bigger trucks on our roads reduces the number of truck trips needed to move the same amount of freight.
Drive axles on tractor units and all trailer axles must be twin tyred for 50MAX truck and trailers, and for B-trains, to meet the 50MAX criteria or neutral pavement wear.
The 50MAX concept relies on neutral pavement wear to be viable on lower strength roads. The TERNZ report(external link) clearly shows the extensive use of twin tyres, therefore 50MAX has always been based on twin tyres in order to retain neutral pavement wear and to enhance the opportunity to grow the 50MAX network.
While the VDAM Rule sets out the dimension requirements for a standard heavy vehicle, Performance Based Standards are used to indicate whether non-standard heavy vehicle designs or combinations meet the safety performance requirements equivalent to a standard vehicle. Find out about Performance Based Standards.