A project was carried out to investigate the impact of four different weighing methods on over/under loading of forestry trucks operating in Forestry Corporation of New South Wales under two types of roads; gazetted (approved for higher legal gross vehicle weight limits) and nongazetted (standard public road gross vehicle weight limits). For all the technologies tested, it was found that there was a substantial under-loading issue ranging from 5.3 to 6.4 tonnes per load on gazetted roads, while the same technology achieved a much better outcome on nongazetted roads with a range of 1.4 tonnes under-loaded to 0.1 tonnes over-loaded on average. There was clearly a large under-loading issue on the gazetted routes. As the same operators with the same technology achieved a much more reasonable outcome on the standard access routes, these results suggest that the GVML available was technically not achievable on the gazetted routes (i.e. not enough volume available to add the weight) or the operators were not aware of or not inclined to load the extra GVML available (i.e. not certain what routes were gazetted or not). As the under load was so consistently close to the extra GVML allowed, the lack of awareness or inclination seems the most likely reasons of under load. The results point also to a more significant role for policy and methods than the technology used for in-forest weighing in achieving effective payload management in forestry haulage.