Understanding GVWR and payload..

That's really weird because GMC Motors says just the opposite on passenger weight being included..

GMC Motors wrote:
Knowing both your vehicle’s gross vehicle weight and gross vehicle weight rating allow you to quickly calculate how much you can safely carry. For example, take a look at the 2016 GMC Sierra 1500 4WD double cab with the EcoTec3 4.3L V6. The gross vehicle weight rating for this particular model is 7,100 pounds†. The weight of the Sierra itself is already 5,216 pounds. By subtracting the weight from the GVWR, you can determine this particular Sierra can carry about 1,884 pounds without exceeding its maximum weight rating.

That doesn’t necessarily mean you can universally carry 1,884 pounds of cargo in its pickup box – the weight of passengers within the cab also needs to be factored into the GVWR. If you have two 200-pound passengers climb into that same Sierra, it now has an available capacity of 1,484 pounds.

It's important to always abide by the GVWR specifically set for your GMC truck or SUV. In the course of vehicle development, professional engineers have extensively pushed these vehicles to their limits in order to keep you, your passengers, and your belongings safe and to avoid damage to your vehicle. Staying within these limits helps your truck, trailer, and travel remain safe.

I guess each vehicle is different,it appears..

And..Who in the heck weighs 150# besides women and teenagers..(laffin)