Page 307 of 436

Checking Coolant
If your vehicle has a diesel engine, see “Checking
Coolant”
in the Diesel Engine Supplement. Adding Coolant
If you need more
coolant, add the proper DEX-COOL@
coolant mixture
at the coolant recovery tank.
The coolant recovery tank is located on the passenger’s
side at the rear corner
of the engine compartment.
When your engine is cold,
the coolant level should be at
the
COLD mark, or a little higher. When your engine is
warm, the level should be up to the HOT mark, or a
little higher.
A CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn you badly.
With the coolant recovery tank, you will almost
never have to add coolant at the radiator.
Never turn the radiator pressure cap
-- even a
little -- when the engine and radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to spill
it.
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.
6-31
~ .
ProCarManuals.com
Page 308 of 436
Radiator Pressure Cap
(Gasoline Engine)
The radiator pressure cap must be tightly installed with
the arrows
on the cap lined up with the overflow tube on
the radiator filler neck.
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed to
prevent coolant loss and possible engine damage
from overheating. Be sure the arrows on the cap line up with the overflow tube on the radiator
filler neck.
Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow
of coolant through the radiator until the coolant
reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
6-32
ProCarManuals.com
Page 309 of 436

Power Steering Fluid
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is a leak in the system or
you hear an unusual noise.
A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How To Check Power Steering Fluid
When the engine compartment is cool, wipe the cap and
the top of the reservoir clean, then unscrew the cap and
wipe the dipstick with a clean rag. Replace the cap and
completely tighten it. Then remove the cap again and
look at the fluid level on the dipstick.
The level should be at the
FULL COLD mark. If
necessary, add only enough fluid to bring the level up
to the mark.
What to Use
To determine what kind of fluid to use, see
“Recommended Fluids and Lubricants” in the Index.
Failure to use the proper fluid can cause leaks and
damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer’s instructions before use. If you
will be
operating your vehicle in an area where the temperature
may
fall below freezing, use a fluid that has sufficient
protection against freezing.
6-33
ProCarManuals.com
Page 311 of 436

Brakes
Brake Fluid
Your brake master cylinder
reservoir is here. It
is filled
with
DOT-3 brake fluid.
There are
only two reasons why the brake fluid level in
the reservoir might go down. The first is that the brake
fluid goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the fluid
level goes back up. The other reason
is that fluid is
leaking out of the brake system.
If it is, you should have
your brake system fixed, since a leak means that sooner
or later your brakes won’t work well, or won’t work
at all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding brake fluid won’t correct a leak.
If you add fluid
when your linings are worn, then
you’ll have too much
fluid when you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is
done on the brake hydraulic system.
I
If you have too much brake fluid, it can spill
on the engine. The fluid will burn if the engine
is hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work is done on the brake
hydraulic system.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections”
in the Index.
ProCarManuals.com
Page 313 of 436

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.
ProCarManuals.com
Page 315 of 436

Battery
Every new vehicle has a Delco Freedom@ battery. You
never have to add water to one
of these. When it’s time
for a new battery, we recommend a Delco Freedom
battery. Get one that
has the replacement number shown
on the original battery’s label.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or more,
take
off the black, negative (-) cable from the battery.
This will help keep your battery from running down.
A CA“T1ON:
Bulb Replacement
Before you replace any bulbs, be sure that all the lamps
are off and the engine isn’t running. See “Replacement
Bulbs”
in the Index for the proper types of bulbs to use.
Halogen Bulbs
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren’t careful. See
“Jump Starting” in the Index
for tips on working around
a battery without
getting hurt.
Contact your dealer to learn how to prepare your vehicle
for longer storage periods.
Also, for your audio system, see “Theft-Deterrent
Feature”
in the Index.
-N:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb.
You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
ProCarManuals.com
Page 345 of 436
Vehicle Identification Number (VIN)
111 111 111111 II
SAMPLE4UXVM072675 IS1 I
ENGINEA7 f 1 ASSEMBLY
CODE MODEL YEAR PLANT
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on the
driver’s side. You can see
it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certification
and Service Parts
labels and the certificates
of title and registration.
Engine Identification
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Parts Identification Label
You’ll find this label on the inside of the glove box. It’s
very helpful
if you ever need to order parts. On this
label is:
your VIN,
the model designation,
0 paint information and
a list of all production options and
special equipment.
Be sure that this label is not removed from the vehicle.
6-69
ProCarManuals.com
Page 348 of 436
2
3
J
D
07
U13
OiQ
03 04
FusdCircuit Breaker Usage
1 Stop/TCC Switch, Buzzer, CHMSL,
Hazard Lamps, Stoplamps
Transfer Case
Courtesy Lamps, Cargo Lamp, Glove
Box Lamp, DomeReading Lamps,
Vanity Mirrors, Power Mirrors
FuseEircuit Breaker
4
10
11
12
13
14
Usage
Instrument Cluster, DRL Relay,
Lamp Switch, Keyless Entry, Low
Coolant Module, Illuminated Entry
Module, DRAC (Diesel Engine)
Not Used
Cruise Control
Auxiliary Power Outlet
Air Bag System
License Lamp, Parking Lamps,
Taillamps,
Roof Marker Lamps,
Tailgate Lamps, Front Sidemarkers,
Fog Lamp Relay, Door Switch
Illumination, Fender Lamps,
Headlamp Switch Illumination
Air Bag System
Wiper Motor, Washer Pump
A/C, A/C Blower, High
Blower Relay
Power Amp, Cigarette Lighter, Door
Lock Relay, Power Lumbar Seat
4WD Indicator, Cluster, Comfort
Controls, Instrument Switches,
Radio Illumination, Chime Module
6-72
ProCarManuals.com