Trying to understand payload

Thanks, Lanerd but I just positively have to understand. I looked up GAW and GAWR. Gaw would be like if I put 500 pounds of rocks in the back end of the truck. My gaw would be on the rear 500 or close to it because I am assuming a tiny bit might go to the front axle. My gawr would be what I am not suppose to exceed but how do you calculate that? I looked up for the Tundra and it said 3900/3800. I am assuming that the GAWR for the front is 3900 and the GAWR for the rear is 3800. The hitch weight would come into play there wouldn't it? Or would it? Surely it would. But what else? Oh, wait! Lets say I have loaded the truck so my payload is 1580. 1000 of that is because of the hitch and some of the trailer contents. That would mean I would have 580 pounds of me, the dogs and lipstick distributed evenly over two axles or four tires, right, because well, we are pretty much sitting in the middle of the truck give or take a bit? So my gaw on the front axle might be 270 but my rear axle would be 1270. Right?