Is hard to find the figures and model variations but basically if you have the towing capacity figure for the model minus 500kg gived a good baseline to to see what it will legally tow, unless its a Cruiser as you load up the tug you loose on the tow as your magic number of the GCM gets closer, it's a broad figure but good rule of thumb because if you are towing near the max it's not really doing anything any good, a 3.5t tow cap dual cab in reality is limited to about 3t max once you load the ute up.