Page 285 of 488
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. 
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        Page 287 of 488

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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Windshield  Wiper Blade Inserts 
To replace the 
windshield wiper 
blade insert, lift 
the 
wiper arm and  rotate 
the blade  until 
it is 
facing  away from the 
windshield. 
Unlatch  the end 
of the insert  from the holding clips. Remove the insert  and 
slide 
a new  one in place.  Make  sure  the blade is secured  in the clips. 
Air  Conditioning 
Every  now and  then have your  dealership  check  your air conditioning 
system to  be sure  it 
has not  lost  any cooling  ability. If you  think the system 
is not working  properly, have your  dealership check it out as soon as 
possi  bleb 
The  air  conditioning  will 
not work when the temperature  is below 40°F 
(4°C). 
Fluid Leak  Check 
After the vehicle has  been  parked for a while, inspect  the surface  under the 
vehicle  for  water, oil, fuel 
or other  fluids.  Water dripping  from the air 
conditioning  system after it has  been  used  is normal. 
If you notice fuel leaks 
or  fumes,  the causes  should be found and corrected at  once. 
Lock Cylinders 
To be sure  your locks operate properly, they  must be lubricated.  Your 
vehicle’s maintenance  schedule  will tell you  how  often to lubricate  them. 
See  “Recommended Fluids  and Lubricants”  in the Index  for 
the proper 
lubricant to use. 
You  should 
not use penetrating  oils because they could  wash out the factory 
installed  lubricant and cause 
the lock to bind.  De-icers  which  contain 
alcohol  could  also 
wash away the lubricant, so be sure  to lubricate  the lock 
after  using 
a de-icer of this type. 
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        Page 323 of 488

Three-  Way  Catalytic  Converter  (Gasoline  Engines) 
Your vehicle’s  three-way  catalytic converter  is designed  to reduce  the 
pollutants 
in your vehicle‘s  exhaust. Use only unleaded  fuel in your vehicle. 
If you  use leaded fuel, you could  damage  your  three-way  catalytic converter 
and  other  engine  components. 
Oxidation  Catalytic  Converter  (Diesel  Engines) 
Your  vehicle’s oxidation  catalytic  converter is designed  to reduce  the 
particulates 
in your vehicle‘s  exhaust. If your vehicle’s oxidation catalytic 
converter  ever needs to  be replaced, 
it must  be  replaced with an oxidation 
converter intended  for use 
with diesel  engines  only. 
Engine  Control  Module  System 
Gasoline Engines 
This  system  has an oxygen  sensor (OS) that helps keep your  engine’s 
air-fuel  mixture at a proper  level. Use only unleaded fuel  in your vehicle.  If 
you  use  leaded fuel, you could  damage  your oxygen  sensor 
(OS) and 
three-way  catalytic converter. 
Diesel Vehicles  Below  8,500 (3 850 Kg) G VWR 
This system monitors  engine speed and throttle position.  It adjusts exhaust 
gas  recirculation  to limit  emissions. 
Malfunction  Indicator  (SERVICE  ENGINE  SOON) 
Light 
The  Malfunction  Indicator  (SERVICE  ENGINE SOON) Light on your 
instrument panel  lets  you  know  when your emission system needs  service. 
The  light will  come on briefly when  you start your  engine to 
let you know 
that  the system  is working.  If 
it does not come  on when  you  start your 
engine,  or 
if it comes on and  stays on while you’re  driving, your system 
may  need  service. Your vehicle  should  still  be driveable,  but  you should 
have your system serviced right away. 
Secondary  Air  Injection  Reaction  (AIR) System 
(Gasoline  Engines) 
You  may  have this  system. It has a control  valve that will direct  air  to where 
it is needed.  If the AIR system needs service, your Malfunction  Indicator 
(SERVICE  ENGINE 
SOON) Lamp on your instrument panel  will come on. 
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NOTICE: 
Don’t  let  anyone tell  you that  underinflation  or  overinflation  is 
all  right.  It’s  not. 
If’ your  tires  don’t  have  enough  air 
(underinflation) 
you can  get: 
0 Too much  flexing 
Too much  heat 
0 Tire  overloading 
Bad  wear 
Bad  handling 
0 Bad  fuel  economy. 
If your  tires  have  too  much  air  (overinflation), you can  get: 
Unusual wear 
Bad  handling 
Rough  ride 
Needless  damage from road  hazards. 
When to Check 
Check your tires once  a month or more. Also, check the  tire pressure  of the 
spare  tire. 
How to Check 
Use a good quality  pocket-type gage to check tire pressure. Simply looking 
at the tires  will not tell  you the pressure, especially 
if you have  radial  tires 
- which  may look properly inflated even  if they’re  underinflated. 
If  your tires have  valve  caps, be sure to put them back  on. They help prevent 
leaks  by keeping  out  dirt and moisture. 
Tire  Inspection  and  Rotation 
Tires should be  inspected  every 6,000 to 8,000 miles (10 000 to 13 000 km) 
for any signs of unusual  wear. If unusual wear  is present, rotate your tires as 
soon as possible  and check  wheel alignment.  Also  check  for  damaged  tires 
or  wheels.  See  “When  it’s Time  for  New Tires” and  “Wheel Replacement” 
later  in this  section  for more  information. 
If your vehicle has dual rear 
wheels,  also  see 
“Dual Tire Operation”  later in this section. 
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        Page 340 of 488

Finish  Damage 
Any stone  chips,  fractures or deep  scratches in the  finish  should be repaired 
right away.  Bare metal will  corrode quickly and may  develop  into 
a major 
repair  expense. 
Minor  chips  and scratches  can  be repaired  with  touch-up  materials available 
from  your  dealer  or  other service outlets.  Larger  areas  of finish  damage  can 
be  corrected  in your dealer’s body and paint shop. 
Underbody  Maintenance 
Chemicals  used for ice and snow removal and  dust control can  collect on 
the underbody.  If these  are  not removed,  accelerated corrosion  (rust) can 
occur 
on the underbody parts  such as fuel  lines,  frame,  floor  pan, and 
exhaust  system even though they have corrosion  protection. 
At  least every  spring, flush these materials from 
the underbody  with plain 
water.  Clean any  areas where  mud and other  debris can collect.  Dirt packed 
in closed areas of the frame  should  be loosened before being  flushed. Your 
dealer  or 
an underbody vehicle washing  system  can  do this for you. 
Chemical  Paint  Spotting 
Some  weather  and atmospheric  conditions  can  create  a  chemical fallout. 
Airborne pollutants  can fall  upon and attack painted  surfaces on your 
vehicle.  This  damage  can  take two  forms:  blotchy, ringlet-shaped 
discolorations,  and small irregular dark spots etched into the paint  surface. 
Although no defect 
in the  paint  job causes  this, GM  will repair,  at no  charge 
to 
the owner, the  surfaces of new vehicles damaged  by this  fallout  condition 
within 
12 months  or 12,000 miles (20 000 km) of purchase, whichever 
comes  first. 
This  applies  only to materials manufactured  and sold  by General  Motors. 
Bodies,  body conversions  or  equipment not made  or sold  by General  Motors 
are  not  covered. 
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        Page 347 of 488
Engine Identification - Gasoline  Engines 
Engine 
Type 
VIN  Code 
Fuel System 
Emissions 
5.0L 
V8 
H 
TBI?  LD 
"Light  Duty  Emissions  with 
8,500 lbs. (3 850 Kg) GVWR  and below. 
**Heavy  Duty Emissions over 8,500 lbs. (3 850 Kg) GVWR. 
?Throttle  Body Injection 
Engine Identification - Gasoline  Engines (cont.) 
Engine 
Type 
VIN  Code 
Fuel  System 
Emissions 7.4L 
V8 
N 
TBI? 
LD*/HD** 
"Light  Duty  Emissions with 8,500 lbs. (3 850 Kg) GVWR and below. 
""Heavy  Duty Emissions  over 
8,500 lbs. (3 850 Kg) GVWR. 
?Throttle  Body  Injection 
Engine Identification - Diesel  Engines 
Engine 
Type 
VIN Code 
Fuel System 
6.5L 
V8 
P 
Diesel 
6.5L 
V8 S 
Turbo  Diesel 
6.5L 
V8 
F 
Turbo Diesel 
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        Page 349 of 488
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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