GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
318 Driving and Operating
If the vehicle has a yellow fuel cap,
E85 or FlexFuel can be used in the
vehicle. SeeE85 or FlexFuel 0319.
For all vehicles except those with
the 6.2L V8 engine, use regular
unleaded gasoline meeting ASTM
specification D4814 with a posted
octane rating of 87 or higher. Do not
use gasoline with an octane rating
below 87, as it may cause engine
damage and will lower fuel
economy.
If the vehicle has the 6.2L V8 engine
(VIN Code J), use premium
unleaded gasoline meeting ASTM
specification D4814 with a posted
octane rating of 91 or higher.
Regular unleaded gasoline rated at
87 octane or higher can be used,
but acceleration and fuel economy
will be reduced, and an audible
knocking noise may be heard. If this
occurs, use a gasoline rated at
91 octane or higher as soon as
possible. Otherwise, the engine
could be damaged. If heavy
knocking is heard when using
gasoline with a 91 octane rating or
higher, the engine needs service. Use of Seasonal Fuels
Use summer and winter fuels in the
appropriate season. The fuels
industry automatically modifies the
fuel for the appropriate season.
If fuel is left in the vehicle tank for
long periods of time, driving or
starting could be affected. Drive the
vehicle until the fuel is at one-half
tank or less, then refuel with the
current seasonal fuel.
Prohibited Fuels
Gasolines containing oxygenates
such as ethers and ethanol, as well
as reformulated gasolines, are
available in some cities. If these
gasolines comply with the
previously described specification,
then they are acceptable to use.
However, E85 (85% ethanol) and
other fuels containing more than
15% ethanol must be used only in
FlexFuel vehicles.Caution
Do not use fuel containing
methanol. It can corrode metal
parts in the fuel system and also
damage plastic and rubber parts.
That damage would not be
covered under the vehicle
warranty.
Some gasolines, mainly high octane
racing gasolines, can contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). Do not use
gasolines and/or fuel additives with
MMT as they can reduce spark plug
life and affect emission control
system performance. The
malfunction indicator lamp may turn
on. If this occurs, see your dealer
for service.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
GMC Sierra Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
9234758) - 2016 - crc - 11/9/15
320 Driving and Operating
refueling to allow the vehicle to
adapt to the change in ethanol
concentration.
Because E85 or FlexFuel has less
energy per liter (gallon) than
gasoline, the vehicle will need to be
refilled more often. SeeFilling the
Tank 0320.
Caution
Some additives are not
compatible with E85 or FlexFuel
and can harm the vehicle's fuel
system. Do not add anything to
E85 or FlexFuel. Damage caused
by additives would not be covered
by the vehicle warranty.
Caution
Do not use fuel containing
methanol. It can corrode metal
parts in the fuel system and also
damage plastic and rubber parts.
That damage would not be
covered under the vehicle
warranty.
Filling the Tank
If the vehicle has a diesel engine,
see the Duramax diesel supplement
for more information.
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
. To help avoid injuries to you
and others, read and follow
all the instructions on the
fuel pump island.
. Turn off the engine when
refueling.
. Keep sparks, flames, and
smoking materials away
from fuel.
. Do not leave the fuel pump
unattended.
. Do not use a cell phone
while refueling.
. Do not re-enter the vehicle
while pumping fuel.
(Continued)
Warning (Continued)
.Keep children away from
the fuel pump and never let
children pump fuel.
. Fuel can spray out if the fuel
cap is opened too quickly.
This spray can happen if the
tank is nearly full, and is
more likely in hot weather.
Open the fuel cap slowly
and wait for any hiss noise
to stop, then unscrew the
cap all the way.