Cadillac 2012 CTS-V Owner's Manual page 340

Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture,
nothing else needs to be added.
This mixture:
Gives freezing protection down
to 37°C ( 34°F), outside
temperature.
Gives boiling protection up to
129°C (265°F), engine
temperature.
Protects against rust and
corrosion.
Will not damage aluminum parts.
Helps keep the proper engine
temperature.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the
coolant changed by an authorized
service center, familiar with legal
requirements regarding used
coolant disposal. This will help
protect the environment and your
health.
The vehicle must be on a level
surface when checking the coolant
level.
The engine coolant reservoir is
located in the engine compartment
on the driver side of the vehicle.
See
.
Check to see if coolant is visible in
the surge tank. If the coolant inside
the surge tank is boiling, do not do
anything else until it cools down.
If coolant is visible but the coolant
level is not at or above the FULL
COLD mark, add a 50/50 mixture
of clean, drinkable water and
DEX-COOL coolant at the coolant
surge tank, but be sure the cooling
system is cool before this is done.
If the engine is warm or hot, the
coolant level should be at or above
the FROID/FULL COLD line on the
side of the coolant surge tank. If the
engine is cold, the coolant level
should be near the FROID/FULL
COLD line on the side of the coolant
surge tank. If it is not, there could
be a leak in the cooling system.