Page 313 of 458

Notice:Using coolant other than
DEX-COOL®may cause premature engine,
heater core, radiator and fuel operated heater
(FOH) corrosion. In addition, the engine coolant
may require changing sooner, at 30,000 miles
(50 000 km) or 24 months, whichever occurs
 rst. Any repairs would not be covered by your
warranty. Always use DEX-COOL
®(silicate-free)
coolant in your vehicle.
What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture.
CAUTION: (Continued)
CAUTION: (Continued)
With plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch  re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and the proper coolant.
Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture 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/retailer check your
cooling system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system.
SeeRecommended Fluids and Lubricants
on page 415for more information.
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        Page 316 of 458

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Just
turn it off and get everyone away from
the vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch  re.
You or others could be badly burned.
Stop your engine if it overheats, and get
out of the vehicle until the engine is cool.
Notice:If your engine catches  re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
If No Steam Is Coming From
Your Engine
If you get an engine overheat warning but see
or hear no steam, the problem may not be
too serious. Sometimes the engine can get a
little too hot when you:
•Climb a long hill on a hot day.
•Stop after high-speed driving.
•Idle for long periods in traffic.
•Tow a trailer. See “Driving on Grades”
underTowing a Trailer on page 269.
If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to
do so, pull off the road, shift to PARK (P)
or NEUTRAL (N) and let the engine idle.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
316 
     
        
        Page 318 of 458

When the engine is cold, the coolant level should
be at or above the COLD FILL mark. If it is
not, you may have a leak at the pressure cap or in
the radiator hoses, heater hoses, radiator, water
pump, or somewhere else in the cooling system.
{CAUTION:
Heater, fuel operated heater (FOH),
radiator hoses, and other engine parts,
can be very hot. Do not touch them.
If you do, you can be burned.
Do not run the engine if there is a leak.
If you run the engine, it could lose all
coolant. That could cause an engine  re,
and you could be burned. Get any leak
 xed before you drive the vehicle.
If there seems to be no leak, start the engine
again. See if the engine cooling fan speed
increases when idle speed is doubled by pushing
the accelerator pedal down. If it does not, your
vehicle needs service. Turn off the engine.Notice:Engine damage from running your
engine without coolant is not covered by
your warranty.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core, or
radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs  rst. Any repairs would
not be covered by your warranty. Always
use DEX-COOL
®(silicate-free) coolant in
your vehicle.
How to Add Coolant to the Coolant
Recovery Tank for Gasoline Engines
If your vehicle has a diesel engine, see
“How to Add Coolant to the Coolant Recovery
Tank” under “Van Models” in the Cooling System
section of the DURAMAX
®Diesel Supplement
for the proper coolant fill procedure.
318 
     
        
        Page 319 of 458

If you have not found a problem yet, but the
coolant level is not at the COLD FILL mark,
add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®engine coolant at the coolant
recovery tank. SeeEngine Coolant on page 312
for more information.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch  re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:
When using concentrated washer  uid,
follow the manufacturer’s instructions
for adding water.
Do not mix water with ready-to-use washer
 uid. Water can cause the solution to
freeze and damage your washer  uid tank
and other parts of the washer system.
Also, water does not clean as well
as washer  uid.
Fill the washer  uid tank only
three-quarters full when it is very cold.
This allows for  uid expansion if freezing
occurs, which could damage the tank if
it is completely full.
Do not use engine coolant (antifreeze) in
your windshield washer. It can damage
the vehicle’s windshield washer system
and paint.
Notice:In cold weather, water can freeze and
crack the engine, radiator, heater core and
other parts. Use the recommended coolant
and the proper coolant mixture.
319 
     
        
        Page 326 of 458

If you add fluid when the linings are worn, then
you will 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.
{CAUTION:
If you have too much brake  uid, it can
spill on the engine and/or fuel operated
heater parts, if equipped. If your vehicle
has a diesel engine and a fuel operated
heater, see “Fuel Operated Heater (FOH)”
in the diesel engine supplement. The  uid
will burn if the engine is hot enough.
You or others could be burned, and your
vehicle could be damaged. Add brake
 uid only when work is done on the brake
hydraulic system. See “Checking Brake
Fluid” in this section.
Refer to the Maintenance Schedule to determine
when to check the brake fluid. SeeScheduled
Maintenance (Gasoline Engine) on page 405.
Checking Brake Fluid
You can check the brake fluid without taking
off the cap.
Look at the brake fluid
reservoir. The fluid level
should be above MIN.
If it is not, have the brake
system checked to see
if there is a leak.
After work is done on the brake hydraulic system,
make sure the level is above the MIN but not
over the MAX mark.
326 
     
        
        Page 339 of 458

These standards apply only to vehicles sold in
the United States.
Federal law prohibits the following acts or the
causing thereof:
1. The removal or rendering inoperative by
any person, other than for purposes of
maintenance, repair or replacement, of any
device or element of design incorporated into
any new vehicle for the purpose of noise
control, prior to its sale or delivery to
the ultimate purchaser or while it is in use; or
2. The use of the vehicle after such device or
element of design has been removed or
rendered inoperative by any person.
Among those acts presumed to constitute
tampering are the acts listed below.
Insulation:
•
Removal of the noise shields or any
underhood insulation.
Engine:
•
Removal or rendering engine speed governor,
if the vehicle has one, inoperative so as to
allow engine speed to exceed manufacturer
specifications.
Fan and Drive:
•
Removal of fan clutch, if the vehicle has one,
or rendering clutch inoperative.
•Removal of the fan shroud, if the vehicle
has one.
Air Intake:
•
Removal of the air cleaner silencer.
•Modification of the air cleaner.
Exhaust:
•
Removal of the muffler and/or resonator.
•Removal of the exhaust pipes and exhaust
pipe clamps.
Fuel Operated Heater (FOH) — Diesel
Engine:
•
Removal of the muffler.
339 
     
        
        Page 390 of 458

Underbody Maintenance
Chemicals used for ice and snow removal
and dust control can collect on the underbody.
If these are not removed, corrosion and rust
can develop on the underbody parts such as
fuel lines, frame, floor pan, fuel operated
heater (FOH) 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 debris can collect.
Dirt packed in close areas of the frame should
be loosened before being flushed. Your dealer
or an underbody car 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 the
vehicle. This damage can take two forms: blotchy,
ring-shaped discolorations, and small, irregular
dark spots etched into the paint surface.
Although no defect in the paint job causes this,
we 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 occurs first.
390 
     
        
        Page 396 of 458
Fuse Usage
5 Back-up Lamps Trailer Wiring
6 Ignition 0
7 Stoplamp
8 Rear Defogger/Heated Mirror
9Right Daytime Running
Lamp/Turn Signal
10Left Daytime Running
Lamp/Turn Signal
11 Truck Body Control Module 4
12 Fuel Pump
13 Trailer
14 Hazard Flashers
15 Horn
16 Truck Body Control Module 3
17 Trailer Stop/Turn Signal
18 Truck Body Control Module 2
19 Truck Body Control Module
20 Remote Function Actuator
21 Engine 2 (Gas), Spare (Diesel)
22 Ignition EFuse Usage
23 Engine 1
24Truck Body Control Module
Ignition 1
25 Spare (Gas), Fuel Heater (Diesel)
26 Inside Rearview Mirror
27 Crankcase
28Brake Transmission Shift
Interlock System
29 Auxiliary Power Outlets
30 Cigarette Lighter
31 Instrument Panel Cluster
32 Air Conditioning
33Spare (Gas), Engine Control
Module (Diesel)
34Canister Vent Solenoid (Gas),
Rear Fog Lamps (Diesel)
35 SPARE
36Brake Transmission Shift
Interlock, Vehicle Back-Up
37 Airbag
396