The tongue weight rating does not include the weight of the hitch. The weight of the hitch will be part of the total amount of weight on the back of the vehicle.

The weight of a blue tongue lizard is 200-500 grams

The tongue of the trailer presses down on the trailer hitch, and that is tongue weight. How hard it presses down is a function of the weight in front of the trailer wheels, and how much of the weight is not offset by the weight behind the wheels. If the tongue weight is too great, the rear of the towing vehicle goes down. Too light, and the boat trailer will swing side to side.

The amount of weight which is placed on the tongue of the drawbar, i.e., the portion which connects to the ball hitch on the tow vehicle.

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