Dexter axle;
The Gross Axle Weight Rating (GAWR) of your running gear is determined by the lowest rated component in the assembly. The capacity of the wheel, tire, axle, brake, springs/rubber and hub are all considered.
This from AL/KO axles says much the same:
** Weigh the trailer after it is fully loaded and ready for use.
Axles, brakes, wheels, tires, frames and suspension components are
designed to carry a specific maximum weight. Locate the VIN
(Vehicle Identification Number) plate on the trailer. It will show the
GVWR (Gross Vehicle Weight Rating). The GVWR is the total
amount your trailer (including tongue weight) can weigh when it is
completely loaded including holding tanks, propane etc. The GAWR
(Gross Axle Weight Rating) is the maximum load that the axles will
carry and the maximum load the brakes will stop.**