Biodiesel - Chevrolet 4500 HD 2023 Manual

228 Driving and Operating

Biodiesel

Biodiesel, may also be referred to as FAME
blended (Fatty-acid methyl ester) fuel is a
renewable fuel produced from vegetable oils
or animal fats that have been chemically
modified to make it compatible with
diesel fuel.
Caution
Do not use home-made biodiesel or home
test kits because the quality cannot be
verified by approved scientific methods.
Do not use raw vegetable oil or other
unmodified bio-oils, fats, 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.
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. Read further to
determine if your driving habits are
compatible with the use of biodiesel.
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.
Owners who use very little fuel, or who
have vehicles or fuel stored for extended
periods of time, should avoid the use of
biodiesel blended fuels above 5% by volume.
When vehicles are stored for longer than
one month, they should be run out of
biodiesel to below one-quarter tank, refueled
with Ultra Low Sulfur Diesel fuel, and driven
several miles before storage.
At temperatures below 0 °C (32 °F), it is
recommended to switch to Ultra Low Sulfur
Diesel fuel with no biodiesel content, or to
blends with biodiesel containing less than
5% by volume. At these extreme cold
temperatures, biodiesel blends higher than
5% by volume may cause fuel filter plugging
and system gelling, which can lead to
vehicle operability problems.
Fuels improperly blended for cold
temperature operation may result in
restricted fuel filters and degraded vehicle
performance. The vehicle may have a fuel
heating system to provide a level of
protection against filter plugging from
gelling or waxing of conventional diesel fuel
and biodiesel blends. If the operating
temperature is far below the temperature at
which gelling or waxing of the fuel occurs,
the system will not prevent all cases of filter
plugging.
If the vehicle experiences a fuel filter
restriction, the on-board monitoring system
will alert the driver that the fuel filter
requires service. The fuel filter, however, will
not prevent all damage caused by poor
quality biodiesel.