Towing Issues: tongue weight, tongue weight, trailer deck

Question
QUESTION: I have read that tongue weight is a % of the trailer weight ranging from 10 to 15 %. I have not seen this weight on a trailer. How is it determined? How do you know what % to use?

ANSWER: That is because the gross weight on the trailer will vary with how much you load on it, including the weight on the trailer.  Here are some examples, If your trailer weighs 2000 pounds empty and load 1000 pounds on the trailer with tongue weight based on 10% is 300 pounds (2000+1000=3000x.10=300). If the trailer weighs 2000 empty and load 3500 pounds on the trailer the tongue weight will be 825 pounds based on 15% (2000+3500=5500x.15=825). Hope this sheds light on the subject.

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QUESTION: Thanks - I think I have a handle on that. Who determines what % to use? Is this something that I can determine?

Answer
The 10-15% rule is the ratio between the tongue weight and the trailer weight regardless of empty or loaded conditions. Many engineers and trailer manufactures have spent a lot on R&D for proper handling and safety concerns which determined the best ratio is 10-15% for tongue weight. You can certainly physically affect the tongue weight. Think of the trailer's axle as a fulcrum and the trailer deck as a slightly balanced lever (remember it's favored 10-15% on one end), you can alter the weight ratio by simply moving the loaded weight on the trailer's deck forward or backward. Ideally, the best weight ratio is having the loaded weight centered and or just slightly forward the trailer's axle. This is how most trailers should be properly loaded and how the trailer manufactures designed them. If you wanted to know exactly what the tongue weight would be then put a scale under the tongue. Hope that helps, if not just let me know.