GMPartsGiant.com offers the wholesale prices for genuine 2020 Buick Regal parts. Parts like Automatic Transmission Park System are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 4 Cyl 2.0L, 6 Cyl 3.6L. Model Code: 1SC 4 DOOR HATCHBACK, 1SL 4 DOOR HATCHBACK, 1SL 4 DOOR STATION WAGON, 1SX 4 DOOR HATCHBACK, BASE 4 DOOR HATCHBACK, BASE 4 DOOR STATION WAGON.