GMPartsGiant.com offers the wholesale prices for genuine 2021 GMC Acadia AWD parts. Parts like Fuel Injector Rail 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, 4 Cyl 2.5L, 6 Cyl 3.6L. Model Code: DENALI SUV, SLE SUV, SLE2 SUV, SLT SUV, SLT2 SUV.