Cadillac 1999 DeVille Owner's Manual page 251

NOTICE:
Engine damage from running your engine
without coolant isn't covered by your warranty.
See "Overheated Engine Protection Operating
Mode" in the Index.
NOTICE:
When adding coolant, it is important that you use
R
-
only DEX COOL (silicate
If coolant other than DEX
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX
covered by your new vehicle warranty.
-
free) coolant.
-
COOL is added to the
--
at
R
-
COOL is not
If there seems to be no leak, with the engine on, check to
see if the electric engine cooling fans are running. If the
engine is overheating, both fans should be running. If
they aren't, your vehicle needs service.
How to Add Coolant to the Coolant
Surge Tank
If you haven't found a problem yet, but the coolant level
isn't at the proper level (2.5 inches (6.4 cm) below the
base of the fill neck), add a 50/50 mixture of clean,
drinkable water and DEX
coolant surge tank, but be sure the cooling system,
including the coolant surge tank pressure cap, is cool
before you do it. (See "Engine Coolant" in the Index
for more information.)
yellowblue
R
-
COOL coolant at the
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