Section 623 is for Commercial Vehicles. Last I knew, and RV wasn't a commercial vehicle.
Sec. 623.011. PERMIT FOR EXCESS AXLE OR GROSS WEIGHT. (a) The department may issue a permit that authorizes the operation of a commercial motor vehicle, trailer, semitrailer, or combination of those vehicles, or a truck-tractor or combination of a truck-tractor and one or more other vehicles:
I'll further help you out, here is the weight restrictions:
Sec. 621.101. MAXIMUM WEIGHT OF VEHICLE OR COMBINATION. (a) A vehicle or combination of vehicles may not be operated over or on a public highway or at a port-of-entry between Texas and the United Mexican States if the vehicle or combination has:
(1) a single axle weight heavier than 20,000 pounds, including all enforcement tolerances;
(2) a tandem axle weight heavier than 34,000 pounds, including all enforcement tolerances;
(3) an overall gross weight on a group of two or more consecutive axles heavier than the weight computed using the following formula and rounding the result to the nearest 500 pounds:
W = 500((LN/(N - 1)) + 12N + 36)
Now if you exceed 20,000 lbs on one axle with your Ram 1500 then you should get a ticket.
