Cadillac 2013 ATS Owner's Manual page 313

mixture, the engine could get too
hot but you would not get the
overheat warning. The engine
could catch fire and you or
others could be burned. Use a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant.
Use a 50/50 mixture of clean
drinkable water and DEX-COOL
coolant. 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.
It is normal to see coolant moving in
the upper coolant hose return line
when the engine is running. It is
also normal to see bubbles entering
the surge tank through the
small hose.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant 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 COLD
FILL line, add a 50/50 mixture of
clean drinkable water and
DEX-COOL coolant.
Be sure the cooling system is cool
before this is done.