If the GCVWR is not posted on the door, it isn't set.

You will notice that there is no GCVWR on the plate on your B pillar... only a GVWR.

in my experience, if you can break the RAWR without breaking the GVWR you have a very interesting weight distribution. Even plow trucks can't normally do this as they are designed to plow or tow, not both.

The GVWR is the number that matters most. The xAWRs are worth paying attention to, but if you sit and do the math, you will likely find that the sum of the axle ratings is more than the GVWR, and the front axle will be about 5-700# below the rating when empty while the rear axle will be very light compared to the rating when empty.

Since trailers this heavy have their own brakes, the pickup is burdened with stopping itself and any of the trailer that it carries, but not the weight that remains on the trailer. Safe tongue weight for a 5th wheel type trailer is 20-25% of the trailer weight.