1981 Chevrolet P40 Submodel: P4T042; 7000lb Front Axle; Drum Brakes; F070; Position: Front Right;. 1982 Chevrolet P40 Submodel: P4T042; 7000lb Front Axle; Drum Brakes; F070; Position: Front Right;. 1983 Chevrolet P40 Submodel: P4T042; 7000lb Front Axle; Drum Brakes; F070; Position: Front Right;.