can't get the gvwr math to work

If you understand that GVWR is a rating putting a vehicle into a particular classification and an identically equipped vehicle can have different ratings based on the buyer’s desired vehicle classification, you understand that GVWR has little to with safety limits. Axle ratings reflect capability better and are based on the weakest components making up that assembly. If you run 19.5” tires and rims, the typically lowest rated component is now stronger resulting in a higher rated assembly. If you take off OEM LT tires and replace them passenger tires or rims, you most likely degraded the axle assembly rating regardless of what is printed.

Blindly following the numbers as an absolute without knowing how they were derived or what is their purpose is the most unsafe practice I have read in these posts.

* Edited for readability