See also:

OnStar®
If equipped, this vehicle has a comprehensive, in-vehicle system that can connect to a live Advisor for Emergency, Security, Navigation, Connection, and Diagnostic Services. See OnStar Overv ...

Recommended Fluids and Lubricants
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Checking Coolant
The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant surge tank. If the coolant inside the coolant surge tank is boiling, do not d ...