The weight of my TT can vary as much as 400 lbs. depending on how much gear I need for each trip.
The sticker on the door jamb should give you the weight of your unloaded truck and it's max cargo capacity.
The combined axle weights of the truck with the TT attached will tell you how much weight you added to the truck when you are loaded for the road.
As long as the weight increase does not exceed the trucks max cargo and each axle is within it rating, you should be good to go.
The change in truck weight when the TT was added gives you the amount of tongue weight that is transferred by the WD hitch to the truck.