It would be easier and more accurate if you fully pack your motorhome and have it weighed.
Subtract that weight from the GCWR -18500 LBS
For example mine is a Four winds 22E (No slides)
fully loaded including passengers and tanks gas water propane =11000 pounds
GCWR 18500
Scaled weight is -11,000
Tow capacity 7,500
I can't exceed the hitch tongue rating of 500 pounds, and though I can reduce my weight I still cannot exceed the hitch rating of 8000 pounds
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