...........you need to do the following. Assumes you take the whole rig to a scale ( three separate in-line scales preferred).
a) place the connected-for-towing TV on one scale and the trailer on another. Weigh each.
b) disconnect the trailer and place all its weight on one scale and weigh it.
c) weigh the truck... both axles on same scale.
d) drive forward so that each truck axle is on a separate scale. Weigh each axle.
Here's the info gleaned:
1) Trailer weight
2) Load on trailer tires when connected with WDH to truck.
3) Total weight of truck.
4) Distribution of weight on each axle whilst disconnected(nearly impossible to have the trailer connected and achieve this) .
What can you do with the numbers?
- trailer weight decrease represents lbs carried on the hitch.
- truck down force increase is that from the tongue. Same number.
What's missing here? Tongue weight and new truck axle (indivdual) load when connected. If connected properly, assume approx 2/3rds of the tongue weight is on the axles(split approx equally). If it's not possible to use the scales to place the trailer tongue on one scale and the wheels on another, then here's a method to weight the tongue at home before connecting.
http://www.rumseytruck.com/product/putnamwt.htm (self explanatory)
Example: Trailer weighs 3800 lbs. Tongue weight (measured before departure) 600 lbs. Trailer connected to TV weighs 3400 lbs. Therefore 400 lbs is on the TV. ASSUMES 2/3..1/3 weight redistribution. As long as the TV squats whilst maintaining its original plane, that assumption is close enuff for 'gumint' work.
If this was unclear, then nevermind.
Denny_A