GMC Duramax Diesel 2015 Owner's Manual page 50

however, it will reduce power and
fuel economy. Avoid using No. 1-D
diesel fuel in warm or hot climates.
It can result in stalling, poor starting
when the engine is hot, and damage
to the fuel injection system. The
fuels industry usually will
automatically modify the fuel for the
appropriate seasonal blend. If in
doubt, please confirm with your
local fuel supplier.
Premium Diesel Fuel
Premium Diesel Fuel (FQP-1A)
corresponding to the Engine
Manufacturers Association (EMA)
Recommended Guideline may
provide less noise, better starting,
and better vehicle performance, but
is not required.
Biodiesel
Biodiesel is a renewable fuel
produced from vegetable oils or
animal fats that have been
chemically modified for normal
performance.
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.
Driving and Operating
Biodiesel blends
Use biodiesel blends that meet the
ASTM specification D6751.
Retail pumps dispensing blends
containing up to 5% biodiesel
(B5) are not required to be
labeled with the concentration of
biodiesel. Blends up to B5 must
meet ASTM D975 (Grades No.
2-D or No. 1-D S15 Ultra Low
Sulfur Diesel).
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.
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