Engine Oil Additives/Engine Oil Flushes

GMC Sierra / GMC Sierra Owners Manuals / Vehicle Care / Vehicle Checks / Engine Oil / Engine Oil Additives/Engine Oil Flushes

Do not add anything to the oil. The recommended oils with the dexos specification and displaying the dexos certification mark are all that is needed for good performance and engine protection.

Engine oil system flushes are not recommended and could cause engine damage not covered by the vehicle warranty.

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