GMC 2003 Envoy XL - Engine Oil Additives; When to Change Engine Oil

As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle.
You should
look for and use only oils which have the
API Starburst symbol and which are also identified
as SAE 5W-30. If you cannot find such SAE 5W-30 oils,
you can use an SAE 1OW-30
oil which has the API
Starburst symbol,
if it’s going to be 0°F (-18°C)
or above.
Do not use other viscosity grade oils, such as
SAE 1OW-40 or SAE 2OW-50 under any conditions.
Notice: Use only engine oil 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.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below -20°F (-29”C), it is
recommended that you 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 engine
at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil (GM Oil
Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and filter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system
to work
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 indicate that an oil change is
necessary. A CHANGE ENG
OIL light in the Driver
Information Center (DIC) will come on. Change your oil
as soon as possible within the next two times you
stop for fuel.
It is possible that, if you are driving under
the best conditions, the oil life system may not
indicate that an oil change is necessary for over
a year.
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