Chevrolet/GMC 6.6L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13337828) - 2020 - CRC - 4/17/19
32 Driving and Operating
Caution (Continued)
or blends of vegetable oil with
diesel. They could damage the
fuel system and engine, and
damages would not be covered
by the vehicle warranty.
Biodiesel Blends
Fuels with a biodiesel content up to
20% by volume may be used (e.g.,
named B20). Only use biodiesel
blends up to 20% by volume that
comply with your country’s or
region’s fuel standards.
Caution
Do not use blends containing
more than 20% biodiesel. Any
engine, fuel system, or exhaust
after-treatment system damage
would not be covered by the
vehicle warranty.
As a renewable fuel, biodiesel
provides some environmental
benefits. However, biodiesel has
unique properties and needs to be
handled differently than diesel fuel.
Its use presents additional risks and
may not be appropriate in all
situations. Certain vehicle operating
modes increase these risks and
should be avoided.
Biodiesel fuel quality degrades with
time and exposure to high
temperature quicker than Ultra Low
Sulfur Diesel fuel. More frequent
refueling provides the best
opportunity to have a supply of fresh
fuel. Storage at hot ambient
temperatures will accelerate
biodiesel degradation.
If the vehicle is not driven often and
uses little fuel, or if it is stored for
extended periods of time, avoid the
use of biodiesel blended fuels
above 5% by volume. When the
vehicle is stored for longer than one
month, it should be run out of
biodiesel to below one-quarter tank,
refueled with biodiesel-free fuel, and
driven several kilometers (miles)
before storage.
Cold Weather Operation
In cold weather, the fuel filter may
become clogged by wax naturally
present in the fuel. To unclog it,
move the vehicle to a warm garage
area and allow the filter to warm up.
The fuel filter may need to be
replaced. See Fuel Filter
Replacement 0 36.
At temperatures below 0 °C (32 °F),
it is recommended to avoid using
biodiesel blends above 5% blend.
This blend may cause fuel filter
plugging, system gelling, and
freezing that may affect vehicle
starting. You may need to turn the
ignition on and off a few times
before the vehicle will start. Also,
idle the vehicle for a couple of
minutes before accelerating.
It is recommended to use Ultra Low
Sulfur No. 1-D diesel fuel or a blend
of No. 1-D and No. 2-D diesel fuel to
enhance vehicle operation in cold
To Next Page
Loading...
Need help?
General
