BTW, if your GCW is 7000 lbs or less, you can use a 350 lb bathroom scale to adjust tongue weight. Mark the center of a short length ( around 4') of 2X4. Make sure the trailer sits level. Set one end of the 2X4 on blocks. Other end on the blocked up scale. Trailer tongue goes over the center of the board mark. Read the scale. You will need to know the GCW. Slowly roll your car (load) forward until you get 10% of the GCW on the scale. Done.