Special Application Services

• Allison Transmission™ Vehicles Only: Replace external transmission filter at first engine oil change only.
• Vehicles with Dual Wheels: Check dual wheel nut torque at 160 km/100 mi, 1 600 km/ 1,000 mi and 9 700 km/6,000 mi.
• Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/ 3,000 mi.
• Have underbody flushing service performed once a year.

    See also:

    Connections
    OnStar Hands-Free Calling allows calls to be made and received from the vehicle. The vehicle can also be controlled from a cell phone through the OnStar mobile app. See www.onstar.com for coverage ...

    Engine Overheating
    If the vehicle has the Duramax® Diesel engine, see the Duramax Diesel Supplement for more information. The vehicle has several indicators to warn of engine overheating. There is a coolant temperatu ...

    Protecting Exterior Bright Metal Parts
    Regularly clean bright metal parts with water or chrome polish on chrome or stainless steel trim, if necessary. For aluminum, never use auto or chrome polish, steam, or caustic soap to clean. A coati ...