
How long  should  you keep  the  coolant  heater plugged in? The answer 
depends  on the weather, 
the kind of oil  you  have, and  some  other  things. 
Follow  this  chart. 
Viscosity/ 
Oil Grade 
SAE 
1 OW-30 
SAE 
15W-40 
32°F to 0°F 
(0°C to -18°C) 
Not 
Required 
Not 
Required 
0°F to -10°F 
(-18OC 
to 
-23 O C) 
Two 
Hours:!: 
Two 
Hours‘% 
Below  -10°F 
Below  -23” 
C 
Eight Hours’> 
or  Overnight 
Eight Hours*  or  Overnight 
’%The times  listed  are minimum  times. 
It will not harm  either  the coolant 
heater  or the  vehicle to leave 
the coolant  heater plugged  in longer  than  the 
times  stated. 
See  “Diesel Fuel  Requirements  and Fuel System’’ 
in the Index  for 
information 
on what fuel to  use in cold weather. 
If Your Diesel Engine  Won’t  Start 
If you‘ve  run out of fuel,  look at  “Running  Out of Fuel”  (see “Diesel Fuel 
Requirements  and Fuel System” 
in the Index). 
If you‘re  not out  of fuel,  and  your engine won’t start, do this: 
Turn your ignition key to RUN.  Make  sure  that the GLOW  PLUGS  light is 
out. Then  IMMEDIATELY  turn the ignition key to START. 
If the light  doesn’t  go off, wait  a few  seconds,  then try starting your  engine 
again.  And, see your  dealer  as  soon as 
you can for  a  starting  system check. 
If the light  comes on and  then  goes off and you  know  your batteries  are 
charged,  but your engine still won’t  start, your vehicle needs  service. 
If the light does not come on when the engine  is cold,  your vehicle needs 
service. 
If  your batteries  don‘t have enough  charge to start  your  engine, see 
“Battery” 
in the Index. 
Be  sure  you have the right  oil for  your  engine,  and that you’ve changed the 
oil  at the  proper  times. If you  use the wrong 
oil, your  engine  may  be  harder 
to  start. 
If  the  engine  starts,  runs a  short  time,  then stops,  your vehicle  needs service. 
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Hesitation  or  “flat”  performance  at  high  speed  or  during  \
hard acceleration 
may  be  an  indication  of premature  fuel  filter  plugging  due  to  dirty  or 
contaminated  fuel.  The fidter  element  may need  to  be  changed 
if this 
happens.  See  your  dealer  for  assistance. 
To drain  water: 
1. Stop and park  the  vehicle  in a  safe  place.  Turn off the  engine  and  apply 
2. Remove  the  fuel  tank  cap. 
the  parking  brake. 
3. Place  a 
fuel-resistant  container  under  the  filter  drain  hose. 
5. 
6. 
7. 
8. 
4. With  the engine 
off,  open  the 
water  drain  valve 
2 to 3 turns. 
When  standing in 
front  of the 
vehicle,  the  valve 
is  located  on  the 
right  side  of the 
thermostat 
housing. 
Start  the  engine  and  allow  it  to  idle  until  clear  fuel  is  ob\
served. 
Stop  the  engine  and close  the  water  drain  valve. 
Remove  the  fuel-resistant  container  and properly dispose of the 
contaminated  fuel. 
To find  out  how  to  properly dispose of contaminated 
diesel  fuel  see  “What  to  Do  with  Used  Oil”  in  the  “E\
ngine  Oil (Diesel 
Engines)”  part,  later  in this  section. 
Install  the  fuel  tank  cap. 
If the  WATER IN FUEL light  comes  on  again  after  driving  a  short  distance 
or  the  engine  runs  rough  or  stalls-a large  amount  of water  has  probably 
been  pumped  into  the 
fuel tank.  The  fuel  tank  should  be  purged. 
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When to Add Oil 
If the  oil  is  at  or below  the ADD mark, then you’ll  need to add  some oil. But 
you must use the right  kind.  This part explains  what kind  of oil  to use.  For 
crankcase  capacity,  see  ”Capacities  and Specifications” 
in the Index. 
NOTICE: 
Don’t  add  too  much  oil. If your engine  has so much oil that  the 
oil  level  gets  above  the  upper 
mark that  shows  the  proper 
operating  range,  your  engine  could  be  damaged. 
The  engine  oil filler  cap  is located  on the  driver’s  side  engine  valve cover. 
Just  fill 
it enough  to  put the level  somewhere in the proper  operating range. 
Push the  dipstick all the way back 
in when  you’re  through. 
What Kind of Oil to Use 
Oils of the proper  quality  for  your vehicle can  be identified  by looking  for 
the  “Starburst”  symbol.  The  “Starburst”  symbol indicates that the  oil has 
been  certified  by the American  Petroleum  Institute 
(API), and is prefenced 
for  use  in your  gasoline  engine. 
If 
you change  your  own oil, be sure you  use oil that has the “Starburst” 
symbol  on the  front 
of the oil container.  If  you have your oil changed  for 
you,  be sure  the 
oil put  into  your  engine  is American  Petroleum Institute 
certified  for  gasoline  engines. 
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HEAVY DUTY EMISSIONS - GASOLINE ENGINES 
RECOMMENDED SAE VISCOSITY  GRADE ENGINE OILS ~  ~  ~~~ 
FOR BEST FUEL  ECONOMY  AND COLD STARTING,  SELECT 
THE LOWEST 
SAE 
VISCOSITY GRADE OIL FOR THE  EXPECTED  TEMPERATURE  RANGE. 
HOT 
WEATHER 
SA€ 5W-30 
LOOK 
FOR THIS 
SYMBOL 
SAE 10W-30 
PREFERRED 
above 0°F (‘1 8°C) 
COLD 
WEATHER 
00 NOT USE SA€ 2OW-50 OR ANY OTHER 
GRADE OIL NOT RECOMMENDED 
As shown in the chart, SAE 10W-30 is best for your vehicle.  However, you 
can  use SAE SW-30 if it’s going  to  be colder  than 60°F (16°C) before your 
next oil change.  When it‘s very cold, you should use SAE 5W-30. These 
numbers  on 
an oil container  show its viscosity, or thickness. Do not  use 
other  viscosity 
oils, such as SAE 2OW-50. 
6- 19 
ProCarManuals.com 

NOTICE: 
Use  only  engine  oil  with  the  American  Petroleum  Institute 
Certified  For  Gasoline  Engines  “Starburst”  symbol.  Failure  \
to 
use  the  proper  oil  can  result  in  engine  damage  not  covered 
by 
your  warranty. 
GM Goodwrench@ oil (in Canada, GM Engine  Oil) meets  all the 
requirements  for your vehicle. 
Engine  Oil  Additives 
Don’t add anything to your oil. Your  GM dealer is ready  to advise if you 
think  something  should be added. 
When to Change  Engine  Oil 
See if any one of these  is true for you: 
Most trips are  less  than 5 to 10 miles (8 to 16 km). This  is particularly 
important  when outside  temperatures  are below freezing. 
Most  trips include  extensive idling (such as frequent driving in stop and 
go traffic). 
Most  trips are through dusty areas. 
You operate  your vehicle in dusty areas or off-road  frequently. 
You frequently tow a trailer. 
If  any  one 
of these  is true  for your vehicle, then  you  need to change your oil 
and  filter  every 
3,000 miles (5 000 km) or 3 months - whichever  comes 
first. 
Light  Duty  Emissions: 
If none  of them is true,  change  the oil and  filter every 7,500 miles  (12 500 
km) or 12 months - whichever  comes  first. 
Heavy Duty  Emissions: 
If none of them is true,  change  the oil and filter  every  6,000  miles (10 000 
km) or 12 months - whichever  comes first. 
6-20 
ProCarManuals.com 

Engine  Coolant  Heater 
An engine  coolant heater can be a big help if you  have to  park outside in 
very  cold weather, 0°F (-1 8OC) or colder.  If your vehicle has this  option, 
see  “Engine  Coolant  Heater’’  in the Index. 
What  to Do with  Used  Oil 
Did you know  that used  engine oil contains  certain elements  that may  be 
unhealthy  for your  skin and  could even cause  cancer?  Don’t let  used  oil stay 
on  your  skin  for very  long. Clean your  skin and nails with  soap and water, 
or  a  good hand  cleaner. Wash or properly  throw away  clothing  or  rags 
containing  used engine  oil.  (See  the manufacturer‘s  warnings about the use 
and  disposal  of 
oil products.) 
Used oil can  be a real  threat to 
the environment.  If you  change  your own oil, 
be sure  to  drain all free-flowing  oil  from the filter  before  disposal.  Don’t 
ever  dispose 
of oil  by putting it in the  trash,  pouring it on the  ground,  into 
sewers,  or into  streams  or bodies 
of water. Instead.  recycle it by taking it to 
a place that  collects used oil. If you have a problem  properly  disposing of 
your used oil, ask your dealer, a service  station  or a local recycling  center 
for  help. 
Engine  Oil (Diesel  Engines) 
It’s a good idea to check  your  engine oil level every  time  you get fuel.  In 
order  to get  an accurate  reading, the  oil must  be  warm  and 
the vehicle  must 
be  on level  ground. 
Turn off the  engine 
and  give  the oil 
a few 
minutes 
to drain  back 
into the 
oil pan. If you 
don’t,  the oil dipstick 
might  not show the 
actual level. 
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ProCarManuals.com 

DIESEL ENGINES 
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS 
SELECT THE SAE GRADE OIL BASE0 ON 
THE EXPECTED TEMPERATURE RANGE 
BEFORE NEXT OIL CHANGE 
HOT 
WEATHER r 
:' F 
I- 100 
+ 60 
+ 32 
0 
-20 
- - 
- 
- -+16 
-3 0 
- - -16 
- - -29 
1 + 
/c3' 
FOR LOOK THIS @ 
SYMBOL 
SAE 1OW-30 
- SAE J 30 
SAE 15W4 
PREFERRED 
above 0°F (-1 8°C) 
WEATHER 
00 NOT USE SAE 2OW-50 OR ANY OTHER 
GRADE OIL NOT RECOMMENDED 
a SAE 15W-40 
As shown  in the viscosity  chart, SAE 15W-40  is best for your  vehicle. 
However,  you  can  use 
SAE IOW-30 if it's going to be colder than 
32°F (0°C) before your next oil change.  When it's very  cold,  below 
0°F (-18"C),  you should  use SAE low-30 to improve cold starting. 
Also, SAE 30 may  be  used  at  temperatures above  freezing, 32°F (0°C). 
These  numbers  on  the 
oil container show its viscosity,  or thickness. Do 
not use other viscosity oils such as SAE 10W-40 or SAE 20W-50. 
6-24 
ProCarManuals.com 

This doughnut-shaped  logo  (symbol) is  used on most oil containers  to help 
you select the correct  oil. 
You  should  look for  this 
on the oil container, and  use only those oils that 
display the  logo. 
GM  Goodwrench‘  oil (in  Canada,  GM  Engine Oil) meets all the 
requirements  for  your vehicle. 
Engine  Oil Additives 
Don’t  add anything  to  your oil. Your  GM dealer  is ready to  advise if you 
think  something  should be added. 
When  to Change  Engine  Oil 
See if any  one  of these  is true  for you: 
0 Most  trips are less than 5 to IO miles (8 to 16 km).  This  is particularly 
important  when outside  temperatures  are  below freezing. 
0 Most trips include  extensive  idling (such as frequent  driving in stop  and 
e 00 traffic). 
0 You operate  your  vehicle in dusty areas  or  off-road  frequently. 
0 You frequently  tow a trailer or use a carrier  on top  of your vehicle. 
If any  of these  is true  for your  vehicle,  then you  need to change  your  oil  and 
filter  every 
2,500 miles (4 000 km) or 3 months - whichever  comes first. 
If  none  of them  is true,  change  the oil and filter  every 
5,000 miles (8 000 
km) or 12 months - whichever  comes  first. 
What to Do with Used Oil 
Did  you  know  that used  engine oil contains  certain elements  that may  be 
unhealthy  for your skin and  could even cause  cancer?  Don‘t let  used  oil stay 
on  your  skin  for very  long.  Clean  your skin and nails  with soap  and water, 
or 
a good  hand cleaner.  Wash or properly throw  away  clothing  or rags 
containing  used engine  oil.  (See the manufacturer’s  warnings  about the use 
and  disposal 
of oil products.) 
Used  oil  can be a real  threat 
to the environment. If you  change  your own oil, 
be  sure 
to drain  all free-flowing  oil from the  filter before  disposal.  Don’t 
ever  dispose  of  oil  by putting  it 
in the trash, pouring it on the ground, into 
sewers,  or into  streams  or bodies  of water.  Instead,  recycle 
it by taking it to 
a  place that  collects used oil. If you  have  a problem properly  disposing of 
your  used  oil, ask your  dealer,  a service station  or  a local recycling  center 
for  help. 
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ProCarManuals.com