GMC 2003 Savana - Manual (Page 248)

Fuel
Use ol the rsiaimnrhefiCled fuel Is art importanl pan of the
proper rraintongnce et your vehicle.
Gasoline Octane
Use regular unleaded gasoline wilh a posted octane
of 07 or higher. H the octane is less than 07, you may
get a heavy knuching noise when you drive, li this
occurs, use a gasoline raied af 07 ociane or higher as
soon as possibtfl. Otherwise, you might damage
your engine. A 1ftUe pinging noise when you accelerate
or drive uphill is considered nonmal. This does riol
indicate a problem exists or that a higher-octane fuel is
necessary. Il you are using 87 octana or higher-octane
fuol and hear heavy knocking, your engine needs
service.
In Canada, look for The
"Auto Makers' Choice"
label on the pump,
Canada Only
Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed t>y the Amerrcgn Autoinobile
ManufEicturors Association and endorsed by [he
Canadian Vehicle Manulaclurers AssocFafion ior better
vehicle performance and engine protection. Gasoline
meelmg these specifications could provide improved
driveability and
omiSEion control system performance
compared to other gasoline.
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