I think you can get enough data by performing several weighs. TV alone, both, front and rear. TV and TT, total rig, front and TT. The latter set should be done twice, with and without the WDH bars engaged. The missing weight would be the hitched rear axle which can be calculated (total rig - TT weight - front axle while hitched).
2013 F-350 CC SB 2WD 6.7PS
2013 Eagle Premier 351 RLTS
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