Mississippi Code Title 63. Motor Vehicles and Traffic Regulations § 63-5-39

(1) The State Tax Commission and county tax collectors, upon registering any vehicle under the laws of this state, when the vehicle is designed and used primarily for the transportation of property or for the transportation of ten (10) or more persons, may require such information and may make such investigations and tests as may be necessary to enable them to determine whether such vehicle may safely be operated upon the highways in compliance with the provisions of this chapter. No vehicle shall be registered for a permissible gross weight in excess of the limitations set forth in this chapter unless a special permit is obtained as provided in Section 63-5-51, nor shall any temporary, trip, or other permit be issued for such vehicle for a gross weight in excess of the limitations set forth in this chapter unless such special permit is obtained. Every vehicle registered shall meet the following requirements:

(2) The State Tax Commission and the county tax collectors shall insert in the registration card issued for every such vehicle the gross weight for which it is registered, and, if it is a motor vehicle to be used for propelling other vehicles, they shall separately insert the total permissible gross weight of such vehicle and other vehicles to be propelled by it. The registration card issued for every such vehicle shall be carried in such vehicle at all times. They may also issue a special plate with such gross weight or weights stated thereon, which shall be attached to the vehicle and displayed thereon at all times. It shall be unlawful for any person to operate any vehicle or combination of vehicles of a gross weight in excess of that for which registered by the State Tax Commission or the county tax collector, or in excess of the limitations set forth in this chapter.