Chevrolet TrailBlazer 2007 Owner's Manual page 401

You should look for this information on the oil
container, and use only those oils that are
identified as meeting GM Standard GM6094M
and have the starburst symbol on the front of the
oil container.
Oils meeting these
requirements should
also have the starburst
symbol on the
container. This symbol
indicates that the oil
has been certified by the
American Petroleum
Institute (API).
Notice: Use only engine oil identified as
meeting GM Standard GM6094M and showing
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 0W-30 oil. Both will
provide easier cold starting and better protection
for the engine at extremely low temperatures.
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