
To Check Coolant 
A 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. 
When your  engine  is cold,  the coolant  level  should  be at the  COLD  mark, or 
a little higher. 
If this  light  comes  on, it means you’re low on  engine  coolant. 
To Add Coolant 
If you need more  coolant,  add the proper  mix ut the surge tmk, but only 
when  the  engine  is cool.  If the  surge tank is empty, see  “Engine 
Overheating” 
in the  Index  for the proper fill procedure. 
A CAUTION: 
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. 
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Brake  Wear 
Your vehicle has  front disc brakes and rear  drum brakes.  If you have a C 
3500 HD model, it has four-wheel  disc brakes. 
Disc brake pads have  built-in wear indicators that make 
a high-pitched 
warning  sound when the brake pads are  worn  and  new pads are needed.  The 
sound  may come  and 
go or be heard  all the time your vehicle  is moving 
(except  when  you  are pushing  on  the brake pedal  firmly). 
I A CAUTION: 
The  brake  wear  warning  sound  means  that  sooner  or  later  your 
brakes  won’t  work  well.  That  could  lead  to  an  accident.  Whe\
n 
you hear  the  brake  wear  warning  sound,  have  your  vehicle 
serviced. 
NOTICE: 
Continuing  to  drive  with  worn-out  brake  pads  could  result in 
costly  brake  repair. 
Some  driving  conditions or  climates  may cause  a brake  squeal  when  the 
brakes  are first applied  or lightly applied.  This  does not  mean something  is 
wrong  with your brakes. 
If you have rear drum brakes,  they don’t  have  wear  indicators,  but if you 
ever  hear 
a rear brake rubbing  noise, have  the rear brake linings inspected. 
Also, the rear brake  drum should  be removed and inspected each time the 
tires  are removed for rotation 
or changing.  When  you  have  the  front brakes 
replaced, have the rear brakes inspected, too. 
Brake linings should always  be replaced as complete  axle  sets. 
Brake  Pedal  Travel 
See your  dealer if the brake  pedal does not return to normal height,  or if 
there is a rapid  increase in pedal  travel.  This  could  be a sign of brake 
trouble. 
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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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0 
e 
0 
0 
0 
0 
C/eaning the Inside of Your Vehicle 
Use a vacuum cleaner often to get  rid of dust  and loose dirt. Wipe vinyl or 
leather  with a clean,  damp  cloth. 
Your 
GM dealer  has two CM cleaners,  a solvent-type  spot lifter and  a 
foam-type  powdered  cleaner. They  will clean normal spots and stains  very 
well.  Do 
not use them  on vinyl  or leather. 
Here  are  some  cleaning tips: 
Always read the instructions  on  the cleaner  label. 
Clean up stains as soon as you  can - before  they set. 
0 Use a clean  cloth or  sponge,  and change  to a clean area often. A soft 
brush  may  be  used 
if stains are  stubborn. 
0 Use solvent-type  cleaners in a well-ventilated  area only. If you use 
them,  don‘t  saturate  the  stained area. 
0 If a ring  forms after  spot  cleaning, clean the entire  area immediately  or 
it will set. 
Using  Foam-Type  Cleaner  on  Fabric 
Vacuum  and  brush the area to remove  any loose dirt. 
Always clean 
a whole  trim panel or section.  Mask surrounding trim 
along  stitch or welt lines. 
Mix Multi-Purpose  Powdered  Cleaner  following the directions on the 
container  label. 
Use  suds 
only and apply with a clean  sponge. 
Don’t saturate  the material. 
Don’t 
rub it roughly. 
As  soon as you’ve  cleaned the section,  use a  sponge  to  remove  the 
suds. 
Rinse the 
section with  a  clean, wet sponge. 
Wipe 
off what’s left with a slightly  damp paper  towel or  cloth. 
Then  dry 
it immediately with a blow dryer  or a heat lamp. 
NOTICE: 
Be  careful. A blow  dryer may scorch  the  fabric. 
~~  ~ 
0 Wipe  with a clean  cloth. 
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Using  Solvent-Type  Cleaner on Fabric 
First,  see  if you have to use  solvent-type  cleaner at all.  Some  spots  and 
stains  will clean 
off better with  just water  and mild  soap. 
If  you  need  to  use a  solvent: 
Gently  scrape  excess  soil from the trim material with a clean, dull knife 
or  scraper.  Use very little cleaner,  light  pressure and clean  cloths 
(preferably  cheesecloth).  Cleaning  should start at the outside of the 
stain,  “feathering”  toward the center. Keep  changing  to 
a clean section 
of the cloth. 
When you clean a stain from  fabric, immediately  dry  the area  with a 
blow  dryer  to help prevent  a  cleaning  ring.  (See  the previous NOTICE.) 
Fabric  Protection 
Your  vehicle has upholstery  and  carpet that has  been  treated with 
Scotchgard TM Fabric Protector, a 3M product.  Scotchgard TN protects fabrics 
by  repelling  oil and  water, which  are the  carriers of most stains. Even  with 
this  protection,  you still need  to clean  your upholstery and  carpet often to 
keep 
it looking  new. 
Further  information 
on cleaning is available  by calling  1-800-433-3296 (in 
Minnesota,  1-800-642-6  167). 
Special Cleaning  Problems 
Greasy or Oily Stains 
Stains  caused by grease,  oil,  butter, margarine,  shoe  polish,  coffee  with 
cream,  chewing  gum,  cosmetic  creams,  vegetable oils, wax crayon,  tar  and 
asphalt can  be removed  as  follows: 
Carefully  scrape off excess  stain. 
Follow the solvent-type  instructions described earlier. 
Shoe polish,  wax crayon,  tar  and asphalt  will stain if left on  a vehicle 
seat  fabric.  They  should be removed  as soon 
as possible.  Be careful, 
because  the cleaner  will dissolve  them and  may cause  them to  spread. 
Non-Greasy  Stains 
Stains  caused by catsup,  coffee  (black),  egg,  fruit, fruit juice, milk,  soft 
drinks,  wine, vomit,  urine and blood can  be removed  as  follows: 
Carefully  scrape  off excess  stain,  then sponge  the soiled area with cool 
water. 
If  a stain remains.  follow the foam-type  instructions  described earlier. 
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If  an odor lingers after cleaning vomit or urine, treat  the area  with  a 
waterhaking  soda solution: 
I teaspoon (5 ml> of baking soda to 1 cup 
(250 ml) of lukewarm  water. 
If needed, clean lightly with solvent-type  cleaner. 
Combination  Stains 
Stains caused  by candy,  ice cream,  mayonnaise, chili  sauce and unknown 
stains can  be removed  as  follows: 
0 Carefully  scrape off excess  stain,  then clean with cool  water  and allow 
to dry. 
0 If a  stain remains, clean it with  solvent-type  cleaner. 
Cleaning  Vinyl 
Use warm water and  a clean  cloth. 
0 Rub with a  clean,  damp  cloth to remove dirt. You  may  have to  do it 
more  than once. 
0 Things  like tar, asphalt  and shoe polish will stain if you don’t get them 
off  quickly.  Use 
a clean cloth and GM vinyMeather cleaner. 
Cleaning  Leather 
Use a soft cloth  with lukewarm water and  a mild  soap  or  saddle  soap. 
For stubborn  stains, use GM vinylheather  cleaner. 
Never use oils,  varnishes,  solvent-based  or abrasive cleaners,  furniture 
polish  or shoe polish on leather. 
0 Soiled  leather  should be cleaned immediately. If dirt is allowed to work 
into  finish, 
it can harm the leather. 
Cleaning  the Top of the  Instrument  Panel 
Use  only mild soap and water to clean the top surfaces of the instrument 
panel.  Sprays  containing  silicones 
or waxes  may cause  annoying reflections 
in the windshield  and even make it difficult to see through the windshield 
under  certain  conditions. 
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Fuse Block 
The fuse block access 
door  is on the  driver’s 
side  edge 
of the 
instrument panel. 
Pull 
off  the  cover  to access 
the fuse block. 
You can  remove  fuses 
with  a fuse extractor. 
The  fuse  extractor  is 
mounted to the  fuse 
block access door. 
To remove  fuses  if  you don’t have  a  fuse extractor, hold the end  of the  fuse 
between  your thumb and index  finger and pull straight out. 
Be  sure  to  use  the correct fuse. If  you  ever have  a problem 
on the  road  and 
don’t have  a  spare  fuse,  you can “borrow”  one 
of the correct  value. Just pick 
some  feature  of your  vehicle that 
you can get along  without-like  the  radio 
or  cigarette  lighter-and  use  its fuse,  if 
it is of the value you need. Replace 
it  as  soon  as  you can.  See “Fuses and Circuit Breakers”  in  the Tndex  for 
more  information. 
Specification Charts 
Replacement  Parts 
Replacement  part numbers listed in this section are based on the latest 
information  available at the  time 
of printing,  and  are subject to  change. If a 
part listed in this manual  is not the same  as the part used in your vehicle 
when  it was built, 
or if  you  have any questions,  please contact your GM 
truck dealer. 
These  specifications  are  for  information 
only. If you have any questions,  see 
the  service  manual  for the  chassis  or refer 
to the body manufacturer’s 
publications. 
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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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