Very Cold Weather Operation - GMC TopKick 2007 Owner's Manual

At a minimum, the diesel fuel you use should meet
the latest version of specification CAN/CGSB-3.517
(Low Sulfur Diesel) in Canada. In addition, the
Engine Manufacturers Association (EMA) has
identified properties of an improved diesel fuel for
better engine performance and durability (FQP-1A).
Diesel fuels corresponding to the EMA description
could provide better starting, less noise, and better
vehicle performance. If there are questions about
the fuel you are using, contact your fuel supplier.
If your vehicle has the 6.6L engine, it is
acceptable to use diesel fuel containing up to
5% biodiesel (B5), but the final blended fuel must
meet the same specification, CAN/CGSB-3.517
(Low Sulfur Diesel) in Canada, as other fuels used
in your vehicle, and the biodiesel used for
making this fuel must meet the latest version of
ASTM specification D 6751. Biodiesel is produced
from vegetable oils or animal fat that have
been chemically modified to reduce the possibility
of damage to your fuel system and engine.
Higher concentration (i.e., greater than B5)
biodiesel-containing fuels or the use of unmodified
bio-oils blended into diesel fuel at any
concentration is not recommended and could
damage your fuel system and engine. Such
damage would not be covered by your warranty. If
there are questions about the biodiesel-containing
fuels you are using, contact your fuel supplier.

Very Cold Weather Operation

Follow the instructions listed previously under the
heading "What Fuel to Use."
Notice: Never use home heating oil or
gasoline in your diesel engine. They can cause
engine damage.
In cold weather, your fuel filter may become
clogged (waxed). To unclog it, move the vehicle to
a warm garage area and warm the filter to
between 32°F and 50°F (0°C to 10°C). You will
not need to replace it. Additional information on the
fuel filter follows.
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