Chevrolet K30 Pickup 1973-1974 Ahead of Rear Axle 16 Gallons Tank. Chevrolet K30 1977-1981 Ahead of Rear Axle 16 Gallons Tank. Chevrolet K20 Pickup 1973-1974 Ahead of Rear Axle 16 Gallons Tank. Chevrolet K20 1975-1981 Ahead of Rear Axle 16 Gallons Tank.