1999 CADILLAC DEVILLE radiator

yellowblue
6-20
To get the right reading, the fluid should be at normal
operating temperature, which is 180F to 200F
(82C to 93C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50F
(10C). If it's colder than 50F (10C), you may have
to drive longer.
Checking the Fluid Level

Park your vehicle on a level place. Keep the
engine running.

With the parking brake applied, place the shift lever
in PARK (P).

With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).

Let the engine run at idle for three to five minutes.Then, without shutting off the engine, follow these steps:
1. The black transaxle fluid cap is located next to the
radiator hose and below the air cleaner assembly on
the driver's side of the engine. Remove the air
cleaner assembly so you can reach the transaxle fluid
cap. The assembly is attached to the vehicle by two
fasteners. Lift up on the air cleaner assembly to
remove it. Find the transaxle fluid cap and turn it
counterclockwise to remove. Pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back out again.

yellowblue
6-22 How to Reset Transaxle Fluid
Change Indicator
Your vehicle is equipped with a transaxle fluid change
indicator. A CHANGE TRANS FLUID message will
display on the Driver Information Center (DIC) when
the powertrain computer determines that the transaxle
fluid needs to be changed or at each 100,000 miles
(160 000 km) interval, whichever occurs first. When this
message appears, change the transaxle fluid and reset
the transaxle fluid life indicator as follows:
1. Turn the ignition on but do not start the engine.
2. Press and hold the OFF and rear defog buttons on the
climate control at the same time until the TRANS
FLUID RESET message appears on the DIC.
Surge Tank Pressure Cap
NOTICE:
The surge tank cap is a 15 psi (105 kPa)
pressure
-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the
cap line up.
If the surge tank pressure cap needs to be replaced, a
GM cap is recommended.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches a preset temperature.
If your thermostat needs to be replaced, a GM
thermostat is recommended.

yellowblue
6-23
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL
engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL
extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, see ªEngine Overheatingº in
the Index.
A 50/50 mixture of clean, drinkable water and
DEX
-COOL
coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 265F (129C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you use
only DEX
-COOL (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX
-COOL is not
covered by your new vehicle warranty.

yellowblue
6-24 What to Use
Use a mixture of one-half clean, drinkable water and
one
-half DEX-COOL
coolant which won't damage
aluminum parts. If you use this coolant mixture, you
don't need to add anything else.
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle's coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn't
get the overheat warning. Your engine could
catch fire and you or others could be burned. Use
a 50/50 mixture of clean, drinkable water and
DEX
-COOL
coolant.
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don't have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.

yellowblue
6-25 Checking Coolant
The surge tank is located next to the engine block on the
passenger's side of the engine.
The cooling system is under a lot of pressure when it is
hot. If the CHECK COOLANT LEVEL message
appears on the Driver Information Center (DIC), you
will need to add coolant.
CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn you badly.
Never turn the surge tank pressure cap
-- even a
little
-- when the engine and radiator are hot.
The vehicle must be on a level surface. When your engine
is cold, the coolant level should be at the full cold mark,
which is 2.5 inches (6.4 cm) below the base of the fill
neck. Use a flashlight as necessary to see into the tank.
If the CHECK COOLANT LEVEL message comes on
and stays on, it means you're low on engine coolant.
For more information, see ªCheck Coolant Level
Messageº in the Index.