Manual says for a F15A Front axle distribution of load is 4065lbs and Rear axle is 5085lbs, total is 9150lbs or 4150kg. I'd say that would be a fair GVM. Unladen mass is easy - take it to your local weighbridge for a weight ticket! It might pay to keep the weight down as rego charges are based on mass, so leave at home things like your toolkit, spare tyre and only half fill one tank
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