It should be in your manual. But forget it; it’s likely a useless number. My manual says I can pull about an 8000# TT. But the tw would be far over my remaining payload for my F150. The best numbers will be to load your TV up with all the gear and people you’ll carry on a trip and weigh it. Subtract that from your TV GVWR and you’ll know what you have left to work with. Keep in mind the closer you get to your total payload the harder it will work on any mountain grades. People who pull near max usually wind up getting a bigger TT.