If you think your weights are close to max I'd suggest weighing the same way you travel. The reason is the weight of your family will be distributed unevenly between the front & rear axles. Someone in the front would have maybe 60% of their weight on the front axle and 40% on the rear. The back seat would be more like 50/50. So if you're close to max...
Probably wouldn't make a huge difference, but...
That's just me.
2013 F-350 CC SB 2WD 6.7PS
2013 Eagle Premier 351 RLTS
-SOLD- 2012 X23B
-SOLD- 2003 Ford Expedition 5.4, Bilstein shocks