GMPartsGiant.com offers the wholesale prices for genuine 2021 GMC Sierra 1500 2WD parts. Parts like Transmission Heat Shield are shipped directly from authorized GM dealers and backed by the manufacturer's warranty. Parts fit for the following vehicle options. Engine: 4 Cyl 2.7L, 6 Cyl 3.0L Diesel, 6 Cyl 4.3L, 8 Cyl 5.3L, 8 Cyl5.3L. Model Code: CREW CAB 5'8" 1/2 TON, CREW CAB 6'6" BOX 1/2 TON, EXTENDED CAB 6'6" BOX 1/2 TON, REGULAR CAB 6'6" BOX 1/2 TON, REGULAR CAB 8' BOX 1/2 TON.