Same question I had over my 81 C2500, but gcw 8500 lb, gvw 8600 lbs! ummmmmmmm so being as gcw is basically a performance standard, does that mean the truck should not be rated to the chassis ability?
Its probably more a how much, who is going to buy that truck per the manufactures people, so it is gvw'd per that end users useage. Sell something to me, I will push axel limits, ie most of us in construction or equal type commercial uses do push our rigs. Hence the lower gvw per total of gaw limits.
At the end of the day, I still feel a given rigs GVW should equal the sum of the GAW's. I can also see how the manufactures will artificially lower the GVW because of many HOA's wordings of no vehicles over 10,000 gvw or 1 ton trucks. Licensing per some states, not all are like here in Wa state where EVERYONE pays tonnage in a pickup, both commercial and personal use. Pretty cut and dry here on over/under 10,0000 lbs vehicles speed limits on freeways, etc. But based on the paid for registration, NOT the door sticker.
Marty