Gasoline Octane
Use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, you may notice an audible knocking noise when you drive, commonly referred to as spark knock. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible.
If you are using gasoline rated at 87 octane or higher and you hear heavy knocking, your engine needs service.
See also:
Engine Drive Belt Routing
3.9L V6 Engine
4.6L V8 Engine ...
General Information
For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:
...
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep
your vehicle in good working condition, but also
helps the environment. All recommended
maintenance is important. Improper vehicle
maintenance can ...