This is a update on my question, Looking at 5vrs. My truck is a 2009 duramax CCSB. The door sticker for gcvw 9200#,it has 3.73 gears, and it weighs approx. 6850# with a half tank of diesel and driver. By the time I add more fuel,another passenger and the hitch it leaves me with 1700# for the pin weight and all the extras I would also be adding.
I have an '08 and the paper that came with the truck showed the weight of tuck as 7010# and gcvw 9200#. Drop 200# for hitch and at least 500# for 40gal aux/tool tank leaves me at best maybe 1500# payload.
My fifth has a gross of around 11000# but there is close to 4000# payload, which leaves a "uvw" of around 7000# putting pin somewhere in
the neighborhood 1400. This is on a trailer of 28ft. I have not weighted it but wouldn't really matter because I certainly wouldn't change trucks or trailer at this point. 6ok on truck and fifth is exactly what we wanted.
I think like others have said that this truck is underrated on payload and if you go by RAWR you have plenty of room to go.
I like what I have. First diesel and if lucky it will last until I quit in 10 or so years.