
Canadian Fuels 
Diesel-powered  trucks  are now  equipped  with emission  control  systems  that 
require  the  use of diesel fuel with  low-sulfur 
(.05% by weight)  content. 
Both  low-  and higher-sulfur  fuels will be  available 
in Canada.  Only 
low-sulfur  diesel fuels  are  available 
in the United  States. It is  important  that 
diesel-powered  trucks  are refueled  with  low-sulfur fuel. Use of fuels  with 
higher-sulfur  content will affect 
the function  of the emission  components 
and may  cause reduced  performance,  excessive  smoke  and unpleasant  odor. 
Cold  Weather  Operation 
Follow the instructions listed previously  under the heading  “What Fuel to 
Use.” 
If  you’re  driving 
in very toold temperatures  and can’t get  a “winterized” 
Number 
2-D that has been  adapted to cold weather  or  a Number 1-D, you 
can 
use one  gallon  of kerosene  for  every two  gallons  of diesel  fuel.  Once 
you  add the  kerosene,  run your  engine  for  several minutes 
so the fuels  will 
mix. Add kerosene  only when the temperature  falls  below 0°F (-1 S”C), 
because  the fuel economy of kerosene  isn’t as good as that  of diesel fuel. 
NOTICE: 
Never  use  home  heating  oil  or  gasoline  in  your  diesel  engine. \
They can  cause  engine  damage. 
In cold weather, your fuel filter  may become  clogged  (waxed). To unclog it, 
warm  the filter  to  between 
32°F and 50°F (OOC to 10°C). You won’t  need 
to  replace 
it. 
Water  in  Fuel 
Sometimes,  water  can be pumped  into your  fuel tank along  with your  diesel 
fuel.  This  can happen 
if a service station  doesn’t regularly  inspect and clean 
its fuel  tanks, or 
if it gets contaminated  fuel  from  its suppliers. 
If  this  happens,  a  WATER 
IN FUEL  light will come on. If it does,  the excess 
water must  be drained.  Your dealer  can  show 
you how to do  this. 
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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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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. 
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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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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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To remove the air  cleaner  filter  on a 6.5 liter turbocharged  diesel  engine, 
first  remove  the rubber  elbow.  Remember  to observe the caution  about 
turbocharger  blades on the rubber elbow. 
Then, unhook the 
cover  retaining  clips 
and  push  the rear 
of 
the cover  toward the 
engine. 
Automatic Transmission Fluid 
When to Check  and  Change 
A good  time  to  check  your  automatic transmission  fluid  level  is  when the 
engine 
oil is  changed.  Refer to the Maintenance  Schedule to determine 
when  to  change  your  fluid.  See  "Scheduled Maintenance  Services'' 
in the 
Index. 
How to Check 
Because  this  operation  can be  a little difficult, you may  choose to have this 
done  at your 
GM dealer  Service  Department. 
If  you  do 
it yourself,  be sure  to follow all the  instructions  here, or you could 
get 
a false  reading  on the  dipstick. 
NOTICE: 
Too much  or  too  little  fluid  can  damage  your  transmission. Too 
much  can mean  that  some of the  fluid  could  come  out  and  fall  on 
hot  engine  parts  or  exhaust  system  parts,  starting  a  fire.  Be \
 sure 
to  get  an accurate  reading  if  you  check  your  transmission  fluid. 
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CranKcase  Capacity 
ENGINE 
4.3L 5  .OL 
5.7L“ 
6.5L 
6.5L 
6.5L 
7.4L>$ 
VIN 
Z 
€4 
K 
P 
S 
F 
N 
QUANTITY WITH 
FILTER* 
4.5 Quarts  (4.3  Liters) 
5 Quarts (4.8 Liters) 
5  Quarts  (4.8  Liters) 
7 Quarts (6.5  Liters) 
7  Quarts 
(6.5 Liters) 
7 Quarts  (6.5 Liters) 
7  Quarts  (6.5  Liters) 
After refill, the  level 
MUST be checked  as outlined  under “Engine  Oil  And 
Filter Recommendations” 
in Section 5. 
All  quantities  are approximate. 
“Add  one  additional quart  for 
C3500 HD Models. 
+Oil filter should  be changed  at EVERY oil change. 
Fuel  Tank  Capacity 
TYPE 
Gasoline/Diesel 
with  Short  Bed 
with  Long  Bed 
Crew  Cab 
Standard 
Chassis-Cab  Models 
Standard  (Side Tank) 
Optional  (Rear Tank) 
3500 HD Models 
Standard  (Side Tank) 
Optional  (Rear Tank) 
QUANTITY 
26 Gallons  (98  Liters) 
34 Gallons 
(1 28  Liters) 
34 Gallons 
(1 28 Liters) 
23  Gallons  (87  Liters) 
3 
1 Gallons (1 17 Liters) 
23 Gallons  (87  Liters) 
3 1 Gallons ( 117 Liters) 
All  quantities  are 
for a completely dry tank  and are approximate. 
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Service  Replacement  Part  and  Filter 
Recommendations 
- Gasoline  Engines 
Engine 4.3L 
VTN Z 
Oil Filter  PFS2 
Air  Cleaner 
A 178CW 
Filter 
PCV  Valve  CV789C 
Spark 
Plugs* .CR43TS 
Fuel Filter  GF48 
1 
Radiator  Cap 
RC36 
5.0L 
H 
PF12183- 
A348C 
cv774c 
.CR43TS 
GF48 
1 
RC36 
5.7L 
K 
PF1218q A348C 
cv774c 
.CR43TS  GF38 
1 
RC36 
+Four  Wheel  Drive  Vehicle 
- use a PFS2  oil filter 
Wse AC  copper-cored  resistor type spark plugs 
Service  Replacement  Part  and  Filter 
Recommendations 
- Diesel  Engines 
Engine 6.5L 6.5L 
VIN P S 
Oil Filter  PF1218 
PF1218 
Air  Cleaner  A644C 
A 1236C 
Fuel  Filter  TP 
1006  TP 
1 006 
Surge 
Tank Cap  RC33  RC33 
7.41 
N 
PF1218 
A348C 
cv774c 
.CR43TS  GF48 
I 
RC36 
6.51 
F 
PF1218 
A 1236C 
TP 
I006 
RC33 
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