
If the differential is at operating temperature (warm),
add enough lubricant to raise the level to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level to 1/2 inch (12 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling system in your vehicle is filled with
new DEX-COOL@ engine coolant. This coolant is
designed to remain in your vehicle for
5 years or
150,000 miles (240
000 km), whichever occurs first,
if
you add only DEX-COOL@ extended life coolant.
The following explains your cooling system and how to
add coolant when
it is low. If you have a problem with
engine overheating, see “Engine Overheating” in
the Index.
A 50/50 mixture of water and the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F (1 29°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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.
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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.
A CAUTION:
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
mix will. Your vehicle’s coolant warning
system is set for the proper coolant
mix. With
plain water or the wrong
mix, 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 mix of clean
water and
DEX-COOL@ coolant.
NOTICE:
If you use an improper coolant mix, your engine
could overheat and be badly damaged. The
repair cost wouldn’t be covered
by your
warranty. Too much water in the mix 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.
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NOTICE:
Using the wrong fluid can badly damage
brake system parts.
For example, just a few
drops of mineral-based oil, such
as engine
oil, in your brake system can damage brake
system parts
so badly that they’ll have to be
replaced. Don’t let someone put in the
wrong kind of fluid.
If you spill brake fluid on your vehicle’s
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on your vehicle. If you do, wash
it off
immediately. See “Appearance Care” in
the Index.
Brake Wear
If you have a C 3500 HD model, it has four-wheel disc
brakes without wear indicators.
If you ever hear a brake
rubbing noise, have the brake linings inspected.
If your pickup is not a
C 3500 HD model, it has front
disc brakes and rear drum brakes. Disc brake pads
(except
C 3500 HD models) 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).
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When 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.
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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:
1.
2.
3.
4.
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.
Fabric Protection
Your vehicle has upholstery and carpet that has been
treated with Scotchgard” Fabric Protector, a
3M
product. It 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:
1. Carefully scrape off excess stain.
2. Follow the solvent-type instructions described earlier.
Shoe polish, wax crayon, tar and asphalt will stain if left
on a vehicle’s seat fabric. They should be removed as
soon as possible. Be careful, because the cleaner will
dissolve them and may cause them to spread.
6-61
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Non-Greasy Stains Cleaning Vinyl
Stains caused by catsup, coffee (black), egg, fruit, fruit
juice, milk,
soft drinks, wine, vomit, urine and blood can
be removed as follows:
1. Carefully scrape off excess stain, then sponge the
soiled area with cool water.
2. If a stain remains, follow the foam-type instructions
described earlier.
3. If an odor lingers after cleaning vomit or urine,
treat the area with a waterhaking soda solution:
1 teaspoon (5 ml) of baking soda to 1 cup (250 ml)
of lukewarm water.
4. 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:
1. Carefully scrape off excess stain.
2. Clean with cool water and allow to dry.
3. If a stain remains, clean it with solvent-type cleaner. 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 a
vinylAeather cleaner. See your dealer for this product.
Cleaning Leather
Use a soft cloth with lukewarm water and a mild soap or
saddle soap and wipe dry with a soft
cloth. Then, let the
leather dry naturally.
Do not use heat to dry.
0 For stubborn stains, use a leather cleaner. See your
dealer for this product.
0 Never use oils, varnishes, solvent-based or abrasive
cleaners, furniture polish or shoe polish
on leather.
dirt is allowed to work into the finish, it can harm
the leather.
0 Soiled leather should be cleaned immediately. If
6-62
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Foreign materials such as calcium chloride and other
salts, ice melting agents, road oil and tar, tree sap, bird
droppings, chemicals from industrial chimneys, etc.,
can damage your vehicle’s finish if they remain on
painted surfaces. Wash the vehicle as soon as possible.
If necessary, use non-abrasive cleaners that are marked
safe for painted surfaces to remove foreign matter.
Exterior painted surfaces are subject to aging, weather
and chemical fallout that can take their toll over a period
of years. You can help to keep the paint finish looking
new by keeping your vehicle garaged or covered
whenever possible.
Protecting Exterior Bright Metal Parts
Bright metal parts should be cleaned regularly to keep
their luster. Washing
with water is all that is usually
needed. However, you may use chrome polish on
chrome or stainless steel trim,
if necessary.
Use special care with aluminum trim.
To avoid
damaging protective trim, never use auto or chrome
polish, steam or caustic soap to clean aluminum.
A
coating of wax, rubbed to high polish, is recommended
for all bright metal parts.
Aluminum or Chrome Wheels
(If Equipped)
Keep your wheels clean using a soft clean cloth with
mild soap and water. Rinse with clean water. After
rinsing thoroughly, dry with a soft clean towel.
A wax
may then be applied.
The surface of these wheels is similar to the painted
surface
of your vehicle. Don’t use strong soaps,
chemicals, abrasive polishes, abrasive cleaners or
abrasive cleaning brushes on them because you could
damage
the surface. You may use chrome polish on
chrome wheels, but avoid any painted surface of the
wheel, and buff off immediately after application.
Don’t take your vehicle through an automatic car wash
that has silicon carbide tire cleaning brushes. These
brushes can also damage the surface
of these wheels.
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Name
ECM-B
RR DEFOG IGN-E
Usage
Fuel Pump, PCMNCM
Rear Window Defogger
Auxiliary Fan Relay Coil,
A/C
Compressor Relay, Hot Fuel
Module, Dual Tanks
Name
FUEL SOL
GLOW PLUG
HORN
AUX FAN
ECM-
1
NC
ENG-
1
LIGHTING
BATT
IGN-A
IGN-B ABS
BLOWER STOP/HAZ
Usage
Fuel Solenoid (Diesel Engine)
Glow plugs (Diesel Engine)
Horn, Underhood Lamps
Auxiliary Fan
Injectors,
PCMNCM
Air Conditioning
lgnition Switch,
EGR, Canister
Purge,
EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
Headlamp and Panel Dimmer
Switch,
Fog and Courtesy Fuses
Battery, Fuse Block Busbar
Ignition Switch
Ignition Switch
Anti-Lock Brake Module
Hi Blower Relay
Stoplamps
6-74
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Normal Maintenance 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.
VIN Code
Oil Filter*
Air Cleaner Filter*
PCV Valve*
Spark Plugs*
Fuel Filter* Wiper Blades**
Wiper Blade Type
Wiper Blade Length
W
PF52
A
1 300C
CV746C
4 1-932
GF626
22 154886
Trico 18 inches (45.0 cm)
M
PF1218T
A 1300C
CV796C
41 -932 GF626
22154886
Trico
18 inches (45.0 cm)
*AC part number
**GM part number
?Use a PF52 oil filter if your vehicle has four-wheel drive.
R
PF1218T
A 1300C
CV796C
4 1-932
GF626
22154886
Trico 18 inches (45.0 cm)
J
PF1218
A 1300C
cv774c
4 1-932
GF626
22154886
Trico
18 inches (45.0 cm)
6-77
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