SDCL § 32-18-21: Multiaxle trucks equipped with vacuum assistor brakes--Vacuum reservoir--Violation as misdemeanor.

Every truck with three or more axles equipped with vacuum assistor type brakes and every truck tractor and truck used for towing a vehicle equipped with vacuum brakes shall be equipped with a reserve capacity or a vacuum reservoir sufficient to ensure that, with the reserve capacity or reservoir fully charged and with the engine stopped, a full service brake application may be made without depleting the vacuum supply by more than forty percent. A violation of this section is a Class 2 misdemeanor.