Chevrolet Caprice 2011 Owner's Manual page 228

10-10 Vehicle Care
Use of oils that do not meet the
dexos specification, however, may
result in reduced performance under
certain circumstances.
Viscosity Grade
SAE 5W-30 is the best viscosity
grade for the vehicle. Do not
use other viscosity oils such as
SAE 10W 30, 10W 40, or 20W-50.
Cold Temperature Operation:
In an area of extreme cold,
where the temperature falls
below 29°C ( 20°F), an
SAE 0W-30 oil should be used.
An oil of this viscosity grade
will provide easier cold starting
for the engine at extremely low
temperatures. When selecting an oil
of the appropriate viscosity grade,
be sure to always select an oil that
meets the required specification,
dexos. See Specification earlier
in this section for more information.