3 passes with 3 pads for the scale tells you almost everything you need to know if you have a WDH 2 passes is enough without WDH. TW and TW% can be calculated with those numbers. And you'll know where tou stand with respect to all your truck's ratings (Axle, GVWR, GCWR, receiver).
Truck
Truck with trailer without WD
Truck with Trailer with WD
The 3 pads are truck front axle, truck rear axle, and TT axles together if more than 1.
TW is calculated by subtracting truck front axle + truck rear axle weights empty from truck front axle + truck rear axle with tongue on ball (no WD).