Recommended Fuel; Gasoline Specifications (U.s. And Canada Only) - GMC 2012 Sierra Series Owner's Manual

9-74 Driving and Operating
Vehicles that have a FlexFuel badge
and a yellow fuel cap can use either
unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85).
See Fuel E85 (85% Ethanol) on
page 9 76. For all other vehicles,
use only the unleaded gasoline
described under Recommended
Fuel on page 9 74.

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.
I n f o r ma t i o n P r o v i d e d b y :
Gasoline Specifications
(U.S. and Canada Only)
At a minimum, gasoline should meet
ASTM specification D 4814 in the
United States or CAN/CGSB 3.5 or
3.511 in Canada. Some gasolines
contain an octane-enhancing
additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. See Fuel Additives
on page 9 75 for additional
information.