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.

    See also:

    Interior
    The Sierra showcases two different interior designs. Work Truck and SLE models are more utility-minded, with large controls and door handles that can be operated while wearing gloves. The SLT offe ...

    Fluids
    Proper fluid levels and approved fluids protect the vehicle’s systems and components. See Recommended Fluids and Lubricants on page 11‑12 for GM approved fluids. • Engine oil and windshield ...

    Compass Zone
    The zone is set to zone eight upon leaving the factory. Your dealer will set the correct zone for your location. Under certain circumstances, such as during a long-distance, cross-country trip or mov ...