Abstract: An airflow regulating device includes a first airflow regulator configured to replace a tractor truck's grille, means for adjusting the first airflow regulator between open and closed configurations, a second airflow regulator positioned inside a housing configured to attach atop the truck's cab, means for adjusting the second airflow regulator between open and closed configurations, and means for actuating each adjustment means. The second airflow regulator may embody either a multiple-louver or a nested-panel formation, and a proximity sensor is included in the means to actuate the adjustment means of the second airflow regulator. The first and second actuation means determine whether the first and second airflow regulators should be in the open or closed configurations and actuate the first and second adjustment means accordingly. The first and second adjustment means then adjust the first and second airflow regulators to the appropriate configurations, improving the truck's gas mileage.