Reactivation for Subsequent Owners
Push 
and follow the prompts to speak to an Advisor as soon as possible after acquiring the vehicle.
The Advisor will update vehicle records and will explain the OnStar service offers and options available.
See also:
Fuel
For diesel engine vehicles, see “Fuel for Diesel Engines” in the Duramax Diesel Supplement.
For Vehicles with gasoline engines, please read this. ...
Four-Wheel Drive
Transfer Case
When to Check Lubricant
Refer to Maintenance Schedule on page 11‑3 to determine when to check the lubricant.
How to Check Lubricant
Electric Shift Transfer Case
A. Fill Plug ...
Warning Lights, Gauges, and Indicators
Warning lights and gauges can signal that something is wrong before it becomes serious enough to cause an expensive repair or replacement. Paying attention to the warning lights and gauges could preve ...