GMC 2010 Sierra - Manual (Page 472)

Filling the Tank
If the vehicle has the DURAMAX Diesel engine, see the
DURAMAX Diesel manual for more information.
{ WARNING:
Fuel vapor burns violently and a fuel fire can
cause bad injuries. 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. Do not smoke near fuel or when
refueling the vehicle. Do not use cellular phones.
Keep sparks, flames, and smoking materials away
from fuel. Do not leave the fuel pump unattended
when refueling the vehicle. This is against the law
in some places. Do not re-enter the vehicle while
pumping fuel. Keep children away from the fuel
pump; never let children pump fuel.
The tethered fuel cap is located behind a hinged
fuel door on the driver side of the vehicle. If the
vehicle has E85 fuel capability, the fuel cap will be
yellow and state that E85 or gasoline can be used.
See Fuel E85 (85% Ethanol) on page 6‑10.
To remove the fuel cap, turn it slowly counterclockwise.
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