GMC 2007 Savana - Manual (Page 291)

To ensure quick starts in the wintertime, the
E85 fuel must be formulated properly for your
climate according to ASTM specification D 5798.
If you have trouble starting on E85, it may be
because your E85 fuel is not properly formulated
for your climate. If this happens, switching to
gasoline or adding gasoline to your fuel tank may
improve starting. For good starting and heater
efficiency below 32°F (0°C), the fuel mix in the fuel
tank should contain no more than 70% ethanol.
It is best not to alternate repeatedly between
gasoline and E85. If you do switch fuels, it
is recommended that you add as much fuel as
possible — do not add less than three gallons
(11 L) when refueling. You should drive the
vehicle immediately after refueling for at least
seven miles (11 km) to allow the vehicle to adapt
to the change in ethanol concentration.
E85 has less energy per gallon than gasoline, so
you will need to refill your fuel tank more often
when using E85 than when you are using gasoline.
See Filling the Tank on page 292.
Notice: Some additives are not compatible
with E85 fuel and may harm your vehicle’s fuel
system. Damage caused by additives would
not be covered by your new vehicle warranty.
Notice: Your vehicle was not designed for
fuel that contains methanol. Do not use
fuel containing methanol. It can corrode metal
parts in your fuel system and also damage
the plastic and rubber parts. That damage
would not be covered under your warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside
the United States or Canada, the proper fuel may
be hard to find. Never use leaded gasoline or
any other fuel not recommended in the previous
text on fuel. Costly repairs caused by use of
improper fuel would not be covered by your
warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business
in the country where you will be driving.
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