Recommended Fuel
Use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, an audible knocking noise, commonly referred to as spark knock, might be heard when driving.
If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. If heavy knocking is heard when using gasoline rated at 87 octane or higher, the engine needs service.
See also:
What to Use
WARNING
Adding only plain water or some other liquid to the cooling system can be dangerous. Plain water and other liquids, can boil before the proper coolant mixture will.
The coolant warning syste ...
Add-on Electrical Equipment
The OnStar system is integrated into the electrical architecture of the vehicle.
Do not add any electrical equipment. See Add-On Electrical Equipment on page 9‑64.
Added electrical equipment ...
Capacities and Specifications
Engine Specifications
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