Fuel; Gasoline Octane; Gasoline Specifications - Chevrolet 2003 Silverado 1500 Pickup Owner's Manual

Fuel
if your vehicle has a diesel engine, see "Diesel Fuel
Requirements and Fuel System" in the Diesel Engine
Supplement.
For vehicles with gasoline engines, please read this.
Gasoline Octane
Use regular unleaded gasoline with a posted octane of 87
or higher. If the octane is less than 87, you may get a
heavy knocking noise when you drive. If this occurs, use
a gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you might damage your engine. A
little pinging noise when you accelerate or drive uphill is
considered normal. This does not indicate a problem
exists or that a higher-octane fuel is necessary. If you are
using 87 octane or higher-octane fuel and hear heavy
knocking, your engine needs service.
Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasoline.
I
Canada Only
In Canada, look for the
"Auto Makers' Choice"
label on the pump.
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