Yes, info will be on door post. The tire loading sticker will tell you how much wt can be added to the truck before going over trucks GVWR. As you know, most FW pin weight is added to the rear axle. You need to be most concerned with the RAWR, and tire max load rating. If you load your truck up, ready to go, everyone, everything, full fuel, and weigh it, you will know your available payload. Most important to weigh just the rear axle, so you will know how much pin wt can be added, before going over RAWR/tire max.
A toy hauler usually has a heavier pin wt, closer to 25 percent. If you loaded the toy hauler to 17K, you may have a pin wt of 4,250. After weighing the truck rear axle, do you have enough left to cover 4K+ pin wt? It may be close, the only way to know is use of scale.
Jerry