The PrePass system is being installed at the weigh station on the westbound lane of Interstate 55/70 in Maryville, IL, just east of St. Louis.
The system will allow Illinois State Police to weigh trucks while they are in motion at highway speeds and electronically check the credentials of trucks equipped with PrePass transponders.
The system in Maryville will open in a few weeks after crews finishing installing the weigh-in-motion scales in the traffic lanes.
About 80 weigh stations nationwide use the PrePass system, with 31 more committed to installing the equipment.
The first PrePass system in Illinois opened in September at a weigh station in the southbound lane of I-55 in Williamsville. The Illinois DOT also plans to install PrePass at weigh stations at Brownstown, Frankfort and Marshall.