Adding Equipment To The Outside Of Your Vehicle; Fuel; Gasoline Octane - Buick 2008 Allure Owner's Manual

Your vehicle has an airbag system. Before attempting
to do your own service work, see Servicing Your
Airbag-Equipped Vehicle on page 1-66.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. See Maintenance Record on page 6-16.
Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This can cause wind
noise and can affect fuel economy and windshield
washer performance. Check with your dealer/retailer
before adding equipment to the outside of your vehicle.

Fuel

Use of the recommended fuel is an important part of
the proper maintenance of your vehicle. To help
keep the engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
The 8th digit of the Vehicle Identification Number (VIN)
shows the code letter or number that identifies your
vehicle's engine. The VIN is at the top left of the
instrument panel. See Vehicle Identification Number
(VIN) on page 5-107.

Gasoline Octane

If your vehicle has the 3.8L V6 engine (VIN Code 2), use
regular unleaded gasoline with a posted octane rating of
87 or higher. If the octane rating is less than 87, you
might 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, the engine needs service.
If your vehicle has the 3.6L V6 engine (VIN Code 7), use
regular unleaded gasoline with a posted octane rating of
87 or higher. For best performance or trailer towing, you
could choose to use middle grade 89 octane unleaded
gasoline. If the octane rating is less than 87, you might
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, the engine needs service.
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