there is 2 things that determine towing capacity, the legal description and common sense...
if you want to tow more then do a search and look at the 80 series that towed a 55 on a braked trailer for an example of what you DO NOT want to end up like...
here it is:
http://forum.ih8mud.com/chit-chat-section/90693-double-cruiser-rollover.html