Page 238 of 378
Downloaded from www.Manualslib.com manuals search engine The  coolant  level  should  be  at  or  above the FULL 
COLD mark. 
If it  isn’t,  you  may  have  a  leak in the  radiator  hoses, 
heater  hoses,  radiator,  water 
pump or  somewhere  else in 
the  cooling  system. 
A CAUTION: 
I 
Heater and radiator  hoses, and  other  engine 
parts,  can be  very  hot.  Don’t  touch  them. 
If you 
do,  you  can  be  burned. 
Don’t  run the engine 
if there  is  a  leak. If you run 
the  engine,  it could  lose  all coolant.  That could 
cause  an engine 
fire, and  you  could  be burned. 
Get  any  leak  fixed  before  you  drive the vehicle. 
NOTICE: 
Engine damage if you  keep  running  your engine 
without  coolant  isn’t  covered  by your warranty. 
See  “Overheated  Engine Protection  Operating 
Mode”  in the  Index. 
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. 
vow vehicle  needs  service. 
5-17   
     
        
        Page 240 of 378
Downloaded from www.Manualslib.com manuals search engine 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  water and 
DEX-COOL@ coolant. 
NOTICE: 
In cold  weather,  water can freeze and  crack  the 
engine,  radiator,  heater core and  other  parts. 
So 
use the recommended  coolant. 
You  can be burned 
if you  spill  coolant on hot 
engine  parts. Coolant  contains  ethylene glycol 
and  it  will burn 
if the engine  parts  are  hot 
enough.  Don’t  spill  coolant  on  a  hot engine. 
5-19   
     
        
        Page 241 of 378
Downloaded from www.Manualslib.com manuals search engine 1. You can  remove  the coolant surge tank  pressure  cap 
when  the cooling system, including  the  coolant surge 
tank  pressure  cap and upper radiator  hose,  is no 
longer  hot.  Turn the pressure  cap slowly  about 
one-quarter  turn to the  left and then  stop. 
If  you  hear a hiss, wait  for that  to  stop. 
A hiss  means 
there  is  still some  pressure left. 
2. Then  keep turning the pressure  cap slowly,  and 
remove  it. 
3. Then  fill  the  coolant  surge tank with  the  proper 
mixture, up  to  the 
FULL COLD mark.   
     
        
        Page 242 of 378
Downloaded from www.Manualslib.com manuals search engine 4. With the coolant surge  tank pressure  cap off, start the 
engine  and  let it run  until you can feel the upper 
radiator hose getting  hot. Watch  out  for  the engine 
cooling fans. 
By this time, the coolant level  inside  the coolant 
surge tank  may be lower.  If the  level  is lower, add 
more  of  the  proper  mixture  to the coolant  surge  tank 
until  the  level reaches the 
FULL COLD mark. 
5. Then  replace  the pressure cap.  Be  sure  the  pressure 
cap  is tight. 
5-21   
     
        
        Page 268 of 378

Downloaded from www.Manualslib.com manuals search engine 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. 
What to Use 
Use a mixture of  one-half clean water (preferably 
distilled) and one-half 
DEX-COOL@ coolant which 
won’t  damage aluminum parts. 
If you use this mixture, 
you  don’t  need 
to add anything else. 
I 
/II CALTTION: 
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  water  and 
DEX-COOL@ coolant. 
6-23   
     
        
        Page 269 of 378
Downloaded from www.Manualslib.com manuals search engine 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. 
Checking Coolant 
The  coolant  surge  tank is in  the  engine  compartment 
behind  the  headlamp.   
     
        
        Page 270 of 378
Downloaded from www.Manualslib.com manuals search engine Turning  the  surge tank pressure  cap when  the 
engine  and radiator  are hot  can  allow  steam  and 
i 
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. 
I 
When  your  engine  is cold,  the coolant level should be  at 
the 
FULL COLD  mark.  Don’t overfill the surge tank. 
Too much coolant  can result  in an ovefflow when the 
fluid  is hot. 
If the  LOW  COOLANT  message comes on, it means 
you’re  low 
on engine  coolant. 
Adding  Coolant 
If you need  more coolant,  add the proper  DEX-COOL@ 
coolant mixture 
at the surge tank, but only when  the 
engine  is cool. 
A CAUTION: 
r 
You  can be burned if you  spill  coolant on hot 
engine  parts. Coolant  contains  ethylene glycol, 
and 
it will  burn  if the  engine  parts  are  hot 
enough.  Don’t  spill  coolant  on  a  hot engine. 
When replacing the pressure cap, make  sure it  is tight. 
6-25   
     
        
        Page 271 of 378
Downloaded from www.Manualslib.com manuals search engine Surge Tank  Pressure  Cap 
NOTICE: 
The  surge  tank  pressure  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. 
When you replace the surge tank pressure cap,  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 pre-set temperature. 
When  you replace the thermostat,  a GM  thermostat 
is  recommended. 
Power  Steering  Fluid 
When  to  Check  Power  Steering Fluid 
It  is  not  necessary to regularly  check  power  steering  fluid 
unless  you  suspect  there  is  a  leak 
in the  system or you  hear 
an unusual  noise. A fluid  loss in this  system  could  indicate 
a  problem.  Have  the  system  inspected 
and repaired.