Cullum Owings Large Truck Safe Operating Speed Act of 2019 This bill directs the Department of Transportation to implement regulations to require (1) all new commercial motor vehicles with a gross weight of 26,001 pounds or more to be equipped with speed-limiting technology, (2) any existing speed-limiting technology already installed in such vehicles to be used while in operation, and (3) the speed-limiting technology to be set to a maximum speed of 65 miles per hour.