The physics of a WDH tranfsfer some of the tongue weight to the front axle, distributing the weight over both front and rear axles on the tow vehicle.

You can increase spring rate to prevent sagging or bottoming and you can go to a higher load range tire, but the axle is only rated to carry "X" amount of weight.

The numbers being discussed here are very minor; probably ok as is. Manufacturers generally design in a safety cushion when they generate rating numbers, figuring the average owner will probably overload without even realizing it.

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Meanwhile, back on the tuna boat.......