SDCL § 32-22-57.1: Vehicle equipped with variable load axle to be equipped with pressure control device--Exception--Violation as misdemeanor.

Any motor vehicle registered in South Dakota which is equipped with a variable load axle or modified thereafter with a variable load axle shall be equipped with a pressure control device. The control for adjusting pressure shall be mounted outside of the driver compartment and shall be preset so the weight carried on the variable load axle may not be varied by anyone in the vehicle. The control for raising and lowering the variable load axle may be accessible to the driver, but it may not also function as the pressure control device. However, this section does not apply to a farm vehicle that is equipped with no more than three axles one of which is a variable load axle. A violation of this section is a Class 2 misdemeanor.