Cadillac 2012 CTS-V Owner's Manual page 332

Selecting the right engine oil
depends on both the proper oil
specification and viscosity grade.
See
Use and ask for licensed engine
oils with the dexos1 approved
certification mark. Engine oils
meeting the requirements for the
vehicle should have the dexos1
approved certification mark.
This certification mark indicates that
the oil has been approved to the
dexos1 specification.
.
SAE 5W 30 is the best viscosity
grade for the vehicle. Do not use
other viscosity grade oils such as
SAE 10W 30, 10W 40, or 20W 50.
If in an area of extreme cold,
where the temperature falls below
20°F ( 29°C), 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, always
select an oil that meets the dexos1
specification or equivalent. See
Specification for more information.
Do not add anything to the oil.
The recommended oils with the
dexos specification and displaying
the dexos certification mark are all
that is needed for good performance
and engine protection.
Engine oil system flushes are not
recommended and could cause
engine damage not covered by the
vehicle warranty.