GMC 2003 Sierra - Manual (Page 396)

As in the chart shown pfe\fiou&ly, SAE 5W-3CI as the
only viscosity grade recommendeil lor your vohicte. V
pu
shouid iook for and use only oils which have the API
Startjurst symbol and v/hich are also fdentitied as
SAE 5W-3Q. II you cannol find such SAE 5W-30 oils,
you can use an SAE lOW-30 oil which has the API
Starburst Symbol, if it's going to be 0“F t-ia*C)
or above. Do not use other viscosity grade oils, such as
SAE 10W-40 tjr SAE 20W-50 under any conditions.
Wofrce: Use only engine ofl with the American
Petroleum Institute Certified For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result In engine damage not covered by
your warranty,
GW Goodwrench^' oil meets aJI the requirements for
your vehicle.
If you are m an area of emreme cold, where the
temperature falls beiow -20“F (■ 2S*'C}. if Is
recommended that yriu use either an SAE 5W*30
synthetic oil or an SAE OW-30 oil. Both will provide
easier cold starting and better protection for your anglr^e
at extremely low tempsraiures.
Engine Oil Additives
Doni add anything to your oil. The recorririnended alts
with ihe starburst symbol are all you will need for
goad performance and engine protection,
When to Change Engine OM (GM Oit
Life System™)
Vour vehicle has a computer system that lels you Know
when lo change the engine oil and fitter. This is
based on engine ravoludons and engine lernparature,
and not on iriileage. Based on driving condilions,
the rnileage al which an oil change will be indicaled can
vary considerably. For Ihe oil life system to worf
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicale Ibat an oil change is
necessary, A CHANGE ENGINE OIL light wilt come on.
Change your oil as soon as possible within thg next
two times you stop for fuel, II is possible [hat, if you are
drtving under the best condiclons, the oil life system
may not Indicate that an oil change is naoassary for over
a year. However, your engine oil and litter must be
changed at least once a year and at this lime the system
musi be rosei. It is also important to check your oil
regularly and Keep it at the proper level.
If the syslern is aver reset accidentaliy. you must
change your oil at 3,000 miles (5000 km) since your
last oil change. Remember to reset Ihe oil liite system
whenever the oil Is changed.
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